This is an appeal by defendant from judgment of conviction for aggravated assault, Minn.St. 609.225, subd. 2. The sole issue raised by defendant is whether Minn.St. 609.11, subd. 1, permitted a minimum 3-year term for this offense, as the district court held. Holding that it did not, we remand for resentencing.
Defendant, pursuant to a plea agreement, pleaded guilty on October 30, 1975, to charges of having committed simple robbery on September 5, 1975; aggravated robbery (using a sawed-off shotgun) on September 20, 1975; and aggravated assault (using a handgun) on September 22, 1975. Other charges against defendant were dismissed pursuant to the plea agreement. The plea agreement contemplated that all the sentences were to run concurrently with each other and with any outstanding sentence defendant would have to complete if his parole were revoked. The parties agreed that defendant should get a 0- to 10-year sentence for simple robbery and a 1-year and 1-day to 10-year sentence for the aggravated robbery, but they disagreed over the sentence defendant should receive for the aggravated assault. The state contended that there should be a 3-year minimum with a 5-year maximum, and defendant contended that the minimum should be only 1 year and 1 day. The disagreement centered on the meaning of § 609.11, subd. 1. The district court held that under the statute the correct minimum term was 3 years. It is this ruling which defendant challenges on appeal.
Section 609.11, subd. 1, provides:
“All commitments to the commissioner of corrections for imprisonment of the defendant are without minimum terms except when sentence is to life imprisonment as required by law and except that any commitment following the defendant’s first conviction of an offense wherein he had in his possession a firearm or used a dangerous weapon at the time of the offense shall be for a term of not less than one year plus one day, nor more than the maximum sentence provided by law for the offense for which convicted, and except that any commitment following defendant’s second or subsequent conviction of an offense wherein he had in his possession a firearm or used a dangerous weapon at the time of the offense shall be for a term not less than three years, nor more than the maximum sentence provided by law for the offense for which convicted, and such person shall not be eligible for parole until he shall have served the full minimum sentence herein provided, notwithstanding the provisions of sections 242.19, 243.05, 609.12 and 609.135. The offenses for which mandatory minimum sentences shall be served as herein provided are: aggravated assault, burglary, kidnapping, manslaughter, murder in the second or third degree, rape, robbery, sodomy, escape while under charge or conviction of a felony, or discharge of an explosive or incendiary device.” (Italics supplied.)
Defendant’s contention is that a commitment to a minimum term of 3 years for a second offense involving a firearm is proper only if the second offense occurred after the conviction for the first offense. Defendant bases this argument in part on the fact that the traditional rule permits sentencing to an increased term under extended term statutes only when the principal offense for which the defendant is convict*910ed and sentenced was committed after conviction of the offense or offenses forming the basis for the extended term. See, e. g., State v. McKenzie, 182 Minn. 513, 235 N.W. 274 (1931).
The state counters by arguing that the rule relied upon by defendant is inapplicable because the statute in question is unambiguous and does not require that the second offense occur after the conviction for the first offense, whereas the extended term statute interpreted in the McKenzie case (L.1927, c. 236, § 2) was a habitual offender statute providing for an increased term for a fourth offense only if the fourth offense occurred after the convictions for the three other offenses. Stated differently, the state argues that if the legislature had intended that the extended minimum term for the second offense involving use of a firearm apply only if that offense occurred after the conviction for the first offense the legislature would have used explicit language to that effect, as it did in enacting the old habitual offender law interpreted in McKenzie and as it did in enacting the present dangerous offender statute, Minn.St. 609.155.1
We believe that in the area of minimum and extended sentences the legislature has an obligation to state its intentions as clearly as possible. When it cannot be said with certainty that the legislature intended to authorize the imposition of a minimum term or an extended term in a particular situation, the presumption must be that the legislature did not intend to do so. This follows partly from the general rule of certainty as to criminal statutes, which is that criminal statutes must be sufficiently clear and definite to inform a person of ordinary intelligence what conduct is punishable and how severe the punishment might be. See, State v. Bell, 280 Minn. 55, 157 N.W.2d 760 (1968). It also follows partly from the fact that the traditional legislative approach has been, as defendant correctly states it, to permit sen-fencing to an increased term under extended term statutes only when the principal offense for which the defendant is convicted and sentenced was committed after conviction of the offense or offenses forming the basis for the extended term. See, in addition to State v. McKenzie, supra, Annotation, 24 A.L.R.2d 1247. Presumably, if the legislature had intended to deviate from the traditional approach taken in habitual offender legislation, it would have done so clearly and explicitly. Here, the legislature did not clearly express an intention that the enlarged minimum term of 3 years apply to a second offense occurring before the conviction of the first offense, and therefore we hold that the district court did not have authority to enlarge the minimum term to 3 years.
Sentence vacated; remanded for resen-tencing.
. Minn.St. 609.155, subd. 2, provides: “Whoever, having previously been convicted of one or more felonies, commits another felony * * * may upon conviction thereof be sentenced to an extended term of imprisonment if [certain conditions are met].”