Judges SOTOMAYOR and KAPLAN filed separate concurring opinions.
POOLER, Circuit Judge.Johney Pham appeals from orders filed on April 12, 2000, October 13, 2000, and November 6, 2000, of the United States District Court for the Southern District of New York (Louis L. Stanton, Judge) denying his habeas corpus petition filed pursuant to 28 U.S.C. § 2255. Pham claims that his trial attorney rendered ineffective assistance when he failed to convey a plea offer to Pham. We have in the record below serial submissions from Pham and serial orders from the district court, and this piecemeal litigation has not created a record from which we can determine that denial of Pham’s petition was appropriate.
Pham had to show that his attorney’s performance was unreasonable considering all of the circumstances and caused Pham prejudice. See Strickland v. Washington, 466 U.S. 668, 688, 694, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984). By incorrectly determining that Pham had suffered no prejudice, the district court did not fully develop its reasoning on the issue of counsel’s deficient performance, the issue we now see as dispositive. A district court has a wide variety of tools available to it in developing the record during habeas proceedings, yet the district court faded to do so here. See Fed. R. Governing Section 2255 Proceedings 4, 7 and 8. The district court, having presided over Pham’s trial and sentencing, also had a close familiarity with the background of petitioner’s claims, yet it failed to draw on this knowledge to make explicit its reasons for finding Pham incredible. We remand to allow the district court another opportunity to review the petition.
BACKGROUND
In October 1995, a trial jury convicted Pham of conspiracy to engage in alien smuggling and hostage taking and conspiracy to receive ransom money, in violation of 18 U.S.C. § 371, conspiracy to commit kidnaping, in violation of 18 U.S.C. § 1201(c), substantive kidnaping, in violation of 18 U.S.C. § 1201(a)(1), receipt of ransom money in connection with a kid-naping, in violation of 18 U.S.C. § 1202, transportation of illegal aliens, in violation of 8 U.S.C. § 1324(a)(1)(B), and concealment and harboring of illegal aliens, in violation of 8 U.S.C. § 1324(a)(1)(C). The government alleged that Pham and multiple co-defendants participated in a kidnap-ing and ransom conspiracy beginning in early 1994 in which they smuggled undocumented Chinese immigrants into the United States and then held them hostage while demanding additional payments from the immigrants’ families. Nine of the defendants pleaded guilty, two — including Pham — sustained convictions after trial, and two others remained fugitives. On November 12, 1997, the district court sentenced Pham to 210 months imprisonment, three years supervised release and $300 special assessment. On October 1, 1998, we affirmed the conviction and sentence by *181summary order. United States v. Wei, 164 F.3d 620 (2d Cir.1998) (table).
On November 29, 1999, Pham filed in district court a pro se habeas corpus petition dated November 2, 1999. The petition raised a number of issues, including a claim of ineffective assistance of trial counsel based on the lawyer’s failure to pursue plea negotiations on Pham’s behalf. In an affirmation filed with the petition, Pham stated that he asked his attorney, Martin J. Siegel, to seek a plea bargain but “Mr. Siegel never communicated to me about whether he sought the plea negotiation, or what the government might have said on that request.” Pham also stated-that he told his lawyer he was willing to plead guilty if he received a sentence of between five and eight years but counsel “never gave [him] an account on whether he approached the government on [his] request, or whether the government said anything on that request.”
The district court summarily denied the petition in a memorandum and order dated April 11, 2000. The district court held that, assuming Pham’s allegations were true, Pham nonetheless failed to demonstrate that “counsel’s performance was outside the wide range of reasonable professional judgment” or that Pham suffered prejudice. On the second point, the district court held that Pham’s claim that he would have taken a plea was frivolous in light of his continued insistence on his innocence.
Pham appealed the order and sought a certificate of appealability (“COA”) in district court, protesting the court’s summary dismissal of his facially valid petition. In a “supplement” to his motion for a COA, Pham informed the district court that he just learned through fulfillment of a Freedom of Information Act request that the government offered co-defendants in his case, including Pham, a global plea bargain but that Pham’s lawyer never told Pham about the offer. By letter dated October 7, 2000, the government responded to Pham’s supplement and attached an affirmation from Pham’s trial counsel. In the affirmation, attorney Siegel stated that he always related plea offers to Pham and discussed them with his client, “but [Pham] always maintained his innocence.” Attached to Siegel’s affirmation was a copy of June 16, 1995, correspondence in which Siegel sent the government’s global plea offer to Pham at the prison in Otisville. In an order dated October 12, 2000, the district court denied Pham’s supplement because the government’s submission “establishes that his lawyer responsibly and timely brought the government’s plea offer to his attention.”
Apparently unaware of the district court’s latest order, Pham sent a letter to the court dated October 17, 2000. In the letter, Pham claimed that Siegel’s affirmation was false and that Pham never received any letters or plea agreements from Siegel while Pham was in Otisville. Pham also denied that Siegel ever visited him at Otisville. According to Pham, the prison’s records would demonstrate that Pham never received the letter that Siegel claimed to have sent. Pham also said that he could prove Siegel never visited through prison records and evidence from the interpreter who would have been present during a visit. The district court responded to Pham’s letter by denying him a COA or an evidentiary hearing in a memorandum endorsement dated November 2, 2000. In a letter to the district court dated October 30, 2000, Pham — again unaware of the court’s order-renewed his request for a hearing or COA and attached an unnotarized statement from a Vietnamese interpreter who said that she “did not accompany Mr. Pham’s lawyer or anyone else to FCI Otisville, New York to trans*182late there, or to take and discuss a plea offer to Mr. Pham at FCI Otisville.” The district court denied the request on November 21, 2000.
By order filed on March 15, 2001, we granted Pham’s pending motion for a COA on the single issue of “whether [Pham’s] counsel failed to advise him of a plea offer made by the government.” Our review of the district court’s denial of a hearing on the habeas petition is for abuse of discretion. Chang v. United States, 250 F.3d 79, 82 (2d Cir.2001). Because it presents a mixed question of law and fact, the issue of whether defendant’s counsel rendered ineffective assistance warrants de novo review. Id.
DISCUSSION
Pham on appeal renews his argument that he received ineffective assistance of counsel because his trial lawyer failed to inform him of the government’s global plea offer. Petitioner also contends that he was entitled to a hearing on this issue. The government responds that the district court properly denied the petition on the record before it because Pham failed to demonstrate with objective evidence either that his lawyer’s performance was deficient or that Pham suffered prejudice.
The parties agree on the relevant legal standards. Defendant suffers a Sixth Amendment violation when he receives ineffective assistance of counsel. In order to prove ineffective assistance, Pham must show (1) “that counsel’s representation fell below an objective standard of reasonableness”; and (2) “that there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different.” Strickland, 466 U.S. at 688, 694, 104 S.Ct. 2052. A defendant suffers a Sixth Amendment injury where his attorney fails to convey a plea offer. Defense counsel have a constitutional duty to give their clients professional advice on the crucial decision of whether to accept a plea offer from the government. Boria v. Keane, 99 F.3d 492, 498 (2d Cir.1996). See also United States v. Gordon, 156 F.3d 376, 379-80 (2d Cir.1998) (per curiam). “Even if there might be circumstances where defense counsel need not render advice as to acceptance of a plea bargain, there can be no doubt that counsel must always communicate to the defendant the terms of any plea bargain offered by the prosecution.” Cullen v. United States, 194 F.3d 401, 404 (2d Cir.1999).
I. Prejudice
Rather than focusing on the first part of the Strickland test, the district court held that Pham failed to show prejudice as the second part of the test requires. Generally, a defendant suffers prejudice if there is a reasonable probability that his reliance on counsel’s ineffective assistance affected the outcome of the proceedings. Gordon, 156 F.3d at 380. The district court in its November 2 order held that Pham presented no objective evidence other than his self-serving statements that he would have accepted the plea offer. It is true that our precedent requires some objective evidence other than defendant’s assertions to establish prejudice. Gordon, 156 F.3d at 380-81. However, a significant sentencing disparity in combination with defendant’s statement of his intention is sufficient to support a prejudice finding. Id. at 381; see also Mask v. McGinnis, 233 F.3d 132, 141-42 (2d Cir.2000), cert. denied, 534 U.S. 943, 122 S.Ct. 322, 151 L.Ed.2d 240 (2001). Both of these elements are present here.
The district court here never considered the undisputed sentencing disparity of at least 113 months between the high *183end of the government’s plea offer and Pham’s sentence after a trial conviction. Instead, the court rejected Pham’s statement that he would have accepted a plea offer of five to eight years. The district court held that “[Pham’s] assertion that he would have pled guilty is belied by the fact that in his § 2255 motion he still claims he is innocent of the charges.” In both its April 11 and November 2 orders, the district court quoted parts of Pham’s habeas petition in support of its conclusion. These quotations in context show that while Pham consistently denied participating in the actual kidnaping and abuse, he admitted participating in certain acts of the conspiracy such as renting a truck to transport the aliens in exchange for $5,000 and procuring a handgun. What the district court also failed to acknowledge was Pham’s assertion that he was unaware of vicarious liability theories that would allow him to be found guilty of a kidnaping or smuggling conspiracy even if he did not participate in certain acts as the government alleged. Contrary to the district court’s assertion, Pham’s petition did not present a blanket claim of innocence.
We have held that where the disparity in potential sentences is great, a finder of fact may infer that defendants who profess their innocence still will consider a plea. Cullen, 194 F.3d at 405, 407 (holding that district court could not overrule magistrate judge’s factual finding on this point without conducting its own hearing). The disparity here was a plea offer of 78 to 97 months and a sentence after trial of 210 months, which is more than double. Our precedent at a minimum indicates that the district court erred in summarily determining the absence of prejudice without even considering the sentence disparity. Mask, 233 F.3d at 141-42; Cullen, 194 F.3d at 407; Gordon, 156 F.3d at 381. This evidence, coupled with the district court’s mischaracterization of Pham’s petition, compels reversal on the prejudice prong. We note that Siegel’s affirmation does not rebut directly Pham’s claims that he was unaware of the sentence disparity or his vulnerability to vicarious liability. Additional evidence therefore was required before the district court could find that Pham would not have pleaded guilty even if he knew of the government’s plea offer.
II. Deficient performance
In its April 11 and November 2 orders, the district court seemed to acknowledge that, taking Pham’s allegations as true, defendant satisfied the first part of the Strickland standard because Pham’s lawyer did not communicate the terms of a plea offer to defendant. There is some subtle confusion on this point due to the piecemeal development of the record and the evolution of Pham’s assertions. At the time of the April 11 order, Pham only claimed that his lawyer failed to pursue plea negotiations, and the district court held that failing to pursue a plea was not deficient performance. By the time of the November 2 order, Pham knew that a plea offer had existed and claimed that his attorney never conveyed the offer to him. If there is any question whether failure to pursue plea negotiations is deficient performance, see Brown v. Doe, 2 F.3d 1236, 1246 (2d Cir.1993), there is no dispute that failure to convey a plea offer is unreasonable performance. Cullen, 194 F.3d at 404. The distinction between failing to pursue and failing to convey plea offers is immaterial here because the district court also found in its October 12 order that the government established, through the affirmation of Pham’s trial counsel, that the “lawyer responsibly and timely brought the government’s plea offer to [Pham’s] attention.” Because it found Strickland’s prejudice prong dispositive, the district *184court’s findings regarding deficient performance are not fully developed.
The government on appeal contends that Pham failed to produce credible, objective evidence in support of his claim. Specifically, the government dismisses Pham’s “self-serving, unnotarized, and in many cases unsworn, statements,” credits the affirmation from Pham’s trial lawyer, criticizes Pham for failing to produce prison records of incoming mail, and discounts the weight of the interpreter’s statement because several different interpreters participated in the multi-defendant case. The government’s arguments only raise issues of fact that should be the subject of additional inquiry in the district court. The government also attempts to foreclose Pham’s arguments by stating that Pham could not have benefitted under the global plea offer because one other co-defendant went to trial. There is evidence, however, that the government did not enforce the “global” provision of its offer because four defendants named in the offer pleaded guilty. We also view as unfair the government’s criticism of Pham for not producing prison mail records during proceedings below where the burden of doing so would be far less on the government than a pro se incarcerated litigant.
Even though Pham demands an eviden-tiary hearing, the government contends that no hearing is required because the paper record contains sufficient material to support the district court’s denial of the petition. It is within the district court’s discretion to determine whether a hearing is warranted. Chang, 250 F.3d at 85-86. Among the wealth of materials available to the district court at its direction are the trial record, letters, documents, exhibits, affidavits and written interrogatories. Fed. R. Governing Section 2255 Proceedings 4, 7. After expanding the record, the district court then decides if an evidentiary hearing also is required. Id. 8. Our precedent disapproves of summary dismissal of petitions where factual issues exists, but it permits a “middle road” of deciding disputed facts on the basis of written submissions. Chang, 250 F.3d at 86.
The circumstances surrounding Pham’s claim may make a hearing unnecessary. For example, the pre-sentence report regarding Pham, which petitioner stated he read and understood, noted that four defendants with whom Pham was indicted pleaded guilty in July 1995. Nonetheless, Pham waited two years after his sentencing before raising the issue of the uncon-veyed plea offer. After his conviction, Pham in an unsuccessful Rule 33 motion challenged his attorney’s performance only on the ground that his lawyer had advised him not to testify even though he must have known about counsel’s additional failure in at least pursuing a possible plea. These circumstances, none of which are in the district court’s decisions, may warrant a finding against Pham.
The district court here merely credited the affirmation of Pham’s trial counsel over Pham’s affirmation and drew inferences adverse to Pham that the record does not support, such as ignoring the sentencing disparity and Pham’s discussion of vicarious liability. In addition, the fact that Pham in his original petition was unaware of the global plea offer lends some weight to his claim of ignorance at the fault of counsel. Indeed, the district court’s decisions suggest that it believed no hearing or even a “middle road” of record development was necessary.
The ultimate issue here is admittedly close, and it may well be that Pham’s allegations lack merit. Nonetheless, the district court abused its discretion in its selective consideration of the record and its failure even to draw upon existing parts of the record to support its conclusions. *185While the district court has wide discretion in developing the record it will use to determine a habeas petition, that discretion does not extend to summary dismissals of petitions presenting facially valid claims and off-the-record interactions with trial counsel. See Chang, 250 F.3d at 85. The record as it presently exists does not support denial of Pham’s petition.
CONCLUSION
For the foregoing reasons, the judgment of the district court is vacated and this matter is remanded for further proceedings in accordance with this opinion.