The government appeals the sentences imposed upon David Victor Gutierrez and Patrick McMickle. The district court departed downward from the range provided by the Federal Sentencing Guidelines (Guidelines) because of defendants’ assistance to the government, notwithstanding the fact that the government did not move for departure. We reverse and remand for resentencing.
I.
Gutierrez and McMickle pleaded guilty to drug charges. After Gutierrez entered his plea, federal agents debriefed him on a single occasion, during which he identified his supplier and his customers. He also testified at another defendant’s trial on drug charges before the same district court.
*350Government agents initially sought McMickle’s cooperation after McMickle delivered eighty-two pounds of marijuana to an undercover agent during a controlled buy. McMickle wore a recording device and returned the marijuana to his source. The government later debriefed McMickle on one occasion.
At the time of Gutierrez’ and McMickle’s sentencing Guidelines § 5K1.1 provided in pertinent part:
Upon motion of the government stating that the defendant has made a good faith effort to provide substantial assistance in the investigation or prosecution of another person who has committed an offense, the court may depart from the guidelines.1
Both Gutierrez and McMickle asked the court to depart from the Guidelines in recognition of their cooperation despite the government’s refusal to move for departure. The court sentenced Gutierrez to fifty-one months’ imprisonment, departing downward from the Guidelines by six months. The court sentenced McMickle to concurrent sentences of ninety-six months’ and sixty months’ imprisonment, a downward departure of twelve months from the applicable Guideline range.
II.
We have upheld refusals to depart downward under section 5K1.1 in the absence of a government motion. See United States v. French, 900 F.2d 1300 (8th Cir.1990); United States v. Sutherland, 890 F.2d 1042 (8th Cir.1989) (per curiam); United States v. Smitherman, 889 F.2d 189 (8th Cir.1989), cert. denied, — U.S. -, 110 S.Ct. 1493, 108 L.Ed.2d 629 (1990); United States v. Grant, 886 F.2d 1513 (8th Cir.1989); United States v. Justice, 877 F.2d 664 (8th Cir.), cert. denied, — U.S.-, 110 S.Ct. 375, 107 L.Ed.2d 360 (1989). In Justice, we said by way of dicta that “in an appropriate case the district court may be empowered to grant a departure notwithstanding the government’s refusal to motion the sentencing court if the defendant can establish the fact of his substantial assistance.” 877 F.2d at 668-69. We held in Smitherman that the absence of a 5K1.1 motion by the government precludes a departure by the trial court in cases that raise no question of prosecutorial bad faith or arbitrariness that might conceivably present a due process issue. Smitherman, 889 F.2d at 191.
Other circuits have similarly found that district courts may not make section 5K1.1 departures absent a government motion. United States v. Wright, 873 F.2d 437 (1st Cir.1989); United States v. Soliman, 889 F.2d 441 (2d Cir.1989); United States v. Huerta, 878 F.2d 89 (2d Cir.1989), cert. denied, — U.S. -, 110 S.Ct. 845, 107 L.Ed.2d 839 (1990); United States v. Francois, 889 F.2d 1341 (4th Cir.1989), cert. denied, — U.S.-, 110 S.Ct. 1822, 108 L.Ed.2d 951 (1990); United States v. White, 869 F.2d 822 (5th Cir.), cert. denied, — U.S.-, 109 S.Ct. 3172, 104 L.Ed.2d 1033 (1989); United States v. Rojas, 868 F.2d 1409 (5th Cir.1989); United States v. Taylor, 868 F.2d 125 (5th Cir.1989); United States v. Lewis, 896 F.2d 246 (7th Cir.1990); United States v. Ayarza, 874 F.2d 647 (9th Cir.1989), cert. denied, — U.S.-, 110 S.Ct. 847, 107 L.Ed.2d 841 (1990). According to the Fourth Circuit, “[t]he language of [section 5K1.1] is clear and unequivocal that consideration of such a departure must begin with a motion of the government.” Francois, 889 F.2d at 1343. The Second Circuit has held that a trial court’s refusal to lower a defendant’s sentence for alleged cooperation with the government is not reviewable, though where the “prosecution declines to certify a defendant as having substantially cooperated with the government, it remains within the district court’s discretion to consider sua sponte the defendant’s allegations upon sentencing.” Soliman, 889 F.2d at 444.
In the present case, the district court reasoned that because section 5K1.1 is labeled as a policy statement, it does not *351have the same force of law as a guideline and therefore is not binding on the court. The government motion requirement is also present, however, in section 3553(e) of the Sentencing Reform Act of 1984:
Upon motion of the Government, the court shall have the authority to impose a sentence below a level established by statute as minimum sentence so as to reflect a defendant’s substantial assistance in the investigation or prosecution of another person who has committed an offense. Such sentence shall be imposed in accordance with the guidelines and policy statements issued by the Sentencing Commission pursuant to section 994 of title 28, United States Code.
18 U.S.C. § 3553(e).
We recently held that a motion by the government is a prerequisite to a district court’s power to impose a sentence below the statutory minimum under section 3553(e). United States v. Coleman, 895 F.2d 501 (8th Cir.1990). Thus, although section 5K1.1 refers to a departure from the Guidelines instead of from a statutory minimum, section 3553(e) shows that the requirement of a government motion for departure actually originated with Congress and not with the Sentencing Commission.
Congress possesses the authority to limit judicial sentencing discretion. United States v. Grant, 886 F.2d 1513, 1514 (8th Cir.1989) (citing Mistretta v. United States, 488 U.S. 361, 109 S.Ct. 647, 650, 102 L.Ed.2d 714 (1989)). “Congress has plenary authority in all areas in which it has substantive legislative jurisdiction so long as exercise of that authority does not offend some other constitutional restriction.” Buckley v. Valeo, 424 U.S. 1, 132, 96 S.Ct. 612, 688, 46 L.Ed.2d 659 (1976) (citation omitted).
Section 5K1.1 implements the Congressional directive of 28 U.S.C. § 994(n), which provides:
The Commission shall assure that the guidelines reflect the general appropriateness of imposing a lower sentence than would otherwise be imposed, including a sentence that is lower than that established by statute as a minimum sentence, to take into account a defendant’s substantial assistance in the investigation or prosecution of another person who has committed an offense.
Congress did not limit the conditions under which the exception may be available in section 994(n), and thus it did not exclude the possibility of a government motion requirement. Instead, Congress introduced the condition itself in 18 U.S.C. § 3553(e), making such a condition presumptively valid in the Guidelines. See United States v. Musser, 856 F.2d 1484, 1486-87 (11th Cir.1988), cert. denied, — U.S.-, 109 S.Ct. 1145, 103 L.Ed.2d 205 (1989) (finding section 3553(e) to fulfill the Congressional directive of section 994(n)).
Beyond the validity of the government motion requirement, we recognize sound policy reasons for placing the discretion to initiate departure with the government. As the Fifth Circuit stated in White, the government motion requirement
is predicated on the reasonable assumption that the government is in the best position to supply the court with an accurate report of the extent and effectiveness of the defendant’s assistance and that it would be the rarest of cases in which the government would be unwilling to recognize that assistance.
869 F.2d at 829. The government may also reward a defendant for substantial assistance in the charging or plea bargaining process instead of moving for departure at sentencing. See Sutherland, 890 F.2d 1043; Justice, 877 F.2d at 669; Taylor, 868 F.2d at 126-27.
In addition, the government’s interest in rewarding defendants for their assistance to government investigations places some control on the prosecution’s discretion. “The reasonable use of substantial assistance motions for those who cooperate will make others more likely to do so in the future.” Huerta, 878 F.2d at 93. Prosecu-torial “promises to make [section 5K1.1] motions ar.e analogous- to plea agreements,” likely making remedies similar to those for breach of a plea agreement also available for breached motion promises. Id. As in Grant, we do not have before us *352the question whether the “prosecutor’s arbitrary or bad faith refusal to move for a section 5K1.1 departure violates due process,” 886 F.2d at 1514.
Therefore, without a clear statement from the Commission to the contrary, we treat the policy statement of section 5K1.1 as binding law because it comports with the directive of section 994(n) and because its requirements coincide with the requirements of section 3553(e). Accordingly, we hold that district courts are bound to comply with the unambiguous language of section 5K1.1.
The sentences imposed upon Gutierrez and McMickle are vacated and the cases are remanded to the district court for re-sentencing.
. Section 5K1.1 was amended effective November 1, 1989, by substituting "provided" for “made a good faith effort to provide.”