I. INTRODUCTION

On May 13, 1992, Abelardo Elenes Gaste-lum pleaded guilty to one count of conspiracy to possess cocaine with intent to distribute ( 21 U.S.C. § 846 ), and one count of possession of cocaine with intent to distribute ( 21 U.S.C. § 841 (a)(1)). Although Fed.R.Crim.Pro. 11(c)(3) requires a district court to inform a defendant of certain constitutional rights “before accepting a plea of guilty,” the court below did not inform Gastelum of those rights until after it had already accepted his guilty plea. The court tried to correct its mistake by subsequently informing Gastelum of his rights. However, the court never gave Gastelum the opportunity to withdraw his guilty plea and to plead anew.

We conclude the district court violated Rule 11(c)(3) by failing to inform Gastelum of his rights until after it had already accepted his guilty plea. We also conclude that the district court’s error was not harmless under Rule 11(h). Accordingly, we are required to VACATE Gastelum’s conviction and plea and to REMAND in order to afford him an opportunity to enter a new plea.

II. FACTS

On May 13, 1992, Abelardo Elenes Gaste-lum pleaded guilty to one count of conspiracy to possess cocaine with intent to distribute ( 21 U.S.C. § 846 ), and one count of possession of cocaine with intent to distribute ( 21 U.S.C. § 841 (a)(1)). 1 The district court accepted Gastelum’s guilty pleas, but it did so without informing him of the constitutional rights that he would be waiving. The gov- *998 emment reminded the court that it had not yet done so, and the court acknowledged its error:

The court attempted to correct the mistake. It then instructed Gastelum on his constitutional rights and asked him whether he understood them. 2 He answered “yes.” However, the court never gave him the opportunity to -withdraw his guilty plea and to plead anew. On appeal, Gastelum contends that the district court violated Fed.R.Crim.Pro. 11(c)(3) by failing to instruct him on his constitutional rights until after it had accepted his guilty plea.

III. ANALYSIS

A The District Court Violated Rule 11(c)(3).

Gastelum argues that the district court violated Fed.R.Crim.Pro. 11(c)(3) because the court did not inform him of certain constitutional rights until after it had accepted his guilty plea. Under Rule 11(c)(3), the district court is required to inform the defendant of certain constitutional rights “before accepting a plea of guilty.” The rule provides in relevant part:

Fed.R.Crim.Pro. 11(c)(3) (emphasis added). 3

As noted above, the record shows that the court below did not inform Gastelum of any constitutional rights before it accepted his plea of guilty. See text supra at p. 1582. Nor did the court give Gastelum the opportunity to withdraw his guilty plea and to plead anew after he had been informed of his rights. Accordingly, the court violated Rule 11(c)(3), which expressly requires that a district inform a defendant of his constitutional rights “before accepting a plea of guilty.” Id. (emphasis added).

The government contends that Gastelum’s prior Rule 11 hearing was sufficient to satisfy the timing requirements of Rule 11(c)(3). We reject this argument. Gastelum’s original plea had been withdrawn by the district court. See United States v. Gastelum, No. CR-F-91-188-OWW (E.D.Ca. Feb. 3, 1992) (granting Gastelum’s motion to withdraw). The earlier Rule 11 proceeding tells us nothing about whether the district court complied with Rule 11(c)(3) in the present proceeding, and it is the present proceeding we must look to exclusively in order to resolve the claims of noncompliance with Rule 11. See, e.g., United States v. Jaramillo-Suarez, 857 F.2d 1368, 1372-73 (9th Cir.1988) (“[T]he dictates of Rule 11 and the federal policy of fair and efficient judicial administration require that the reviewing court look solely to the record of the plea proceeding.” (emphasis added)); see also *999 United States v. Kamer, 781 F.2d 1380, 1383 (9th Cir.) (“[C]laims of noncompliance with [R]ule 11 must be resolved solely on the basis of the [R]ule 11 transcript. The transcript provides all that is needed and all that is allowed for the resolution of such claims.” (emphasis added and internal quotes omitted)), ce rt. denied, 479 U.S. 819 , 107 S.Ct. 80 , 93 L.Ed.2d 35 (1986). This requirement ensures that a defendant is fully aware of his rights when his plea is entered — that he is aware of them at the time they are being waived. Earlier or later knowledge is insufficient to provide that assurance. Accordingly, the government’s argument fails. 4

B. The Error Was Not Harmless.

The government argues that even if the district court erred in applying Rule 11(c)(3), the error was harmless under Fed.R.Crim.Pro. 11(h). Rule 11(h) provides:

The government contends that the district court’s error did not affect the defendant’s “substantial rights” because the court subsequently informed the defendant of his constitutional rights. We disagree.

The harmless error clause of Rule 11 permits us to uphold guilty pleas only when there has been “a minor or technical violation of Rule 11.” United States v. Graibe, 946 F.2d 1428, 1433 (9th Cir.1991). For example, in United States v. Rubalcaba, 811 F.2d 491 (9th Cir.), cert. denied, 484 U.S. 832 , 108 S.Ct. 107 , 98 L.Ed.2d 66 (1987), we held that an instruction telling the defendant he was waiving his right to a “trial” instead of a “jury trial” was harmless. See id. at 493 .

As the advisory committee to Rule 11(h) has noted, “the kinds of Rule 11 violation which might be found to constitute harmless ‘error upon direct appeal are fairly limited.” Fed.R.Crim.Pro. 11(h), Notes of Advisory Committee to the 1983 Amendment (emphasis added). 5 We must reverse guilty pleas whenever the district court’s violation of Rule 11 affects a defendant’s “substantial rights.” Put differently, we must reverse if the violation would “nullify or dilute important Rule 11 safeguards.” See, e.g., Jaramillo-Suarez, 857 F.2d at 1371 .

We hold that the district court’s failure to follow the timing requirements of Rule 11(c)(3) nullified a critical Rule 11 safeguard. The district court’s error goes to the very heart of what Rule 11(c)(3) was intended to prevent — an unintelligent or uninformed waiver of important constitutional rights. That waiver occurs at the moment the defendant pleads guilty. See Boykin v. Alabama, 395 U.S. 238, 242-44 , 89 S.Ct. 1709, 1712-13 , 23 L.Ed.2d 274 (1969). We have previously explained that “Rule 11 is designed to ensure that the defendant is aware of his fundamental rights before he pleads guilty, not that he will become aware of those rights some time after the plea.” See Graibe, 946 F.2d at 1434 (emphasis added). To put our explanation even more precisely: the rule is designed to ensure that the defendant is aware of those rights at the time he pleads guilty.

In any event, the essential requirement of Rule 11(c)(3) — that the defendant be *1000 placed in a position where his plea will be intelligent and informed — was simply not met. The district court’s post hoc attempt to instruct Gastelum of his constitutional rights did not cure the violation — Gastelum had already entered his' guilty plea. Thus, the violation was neither minor nor technical.Rather than attempting to correct it retroactively, the court should have given Gastelum the opportunity to withdraw his plea and to plead anew. 6

C. Summary.

In sum, the district court’s failure to follow Rule 11(c)(3) affected Gastelum’s “substantial rights.” The district court’s error deprived him of a significant protection afforded by that rule: specifically, an explanation by the court of his constitutional rights before he entered the plea that served to waive them. Thus, the error cannot be harmless under Rule 11(h). We are required to vacate Gastelum’s plea and to give him an opportunity to enter a new one. See McCarthy v. United States, 394 U.S. 459, 468-72 , 89 S.Ct. 1166, 1172-74 , 22 L.Ed.2d 418 (1969). 7

IV. CONCLUSION

We conclude that the district court violated Rule 11(c)(3) by failing to instruct Gastelum of his rights until after he had already pleaded guilty. Because that error affected his substantial rights, it was not harmless under Rule 11(h). Accordingly, we are required to VACATE Gastelum’s conviction and plea and to REMAND so that the district court may afford him the opportunity to enter a new plea.

VACATED and REMANDED.

. Gastelum had initially pleaded guilty to the two counts, but then asked to withdraw his plea after he learned that he would remain in the custody of the state for several weeks until his sentencing hearing. The district court granted Gastelum's request because his original plea was not knowing and intelligent. Gastelum returned a few weeks later, however, and again pleaded guilty.

. These rights included Gastelum's right to a public and speedy trial, to the selection of an unbiased jury, to his privilege against self-incrimination, to the government’s burden of proof, to cross-examine government witnesses, to challenge the government’s evidence, to introduce his own evidence, to call and subpoena his own witnesses, and to receive a unanimous verdict. The district court asked Gastelum whether he agreed to waive these rights. Although Gastelum expressly agreed to waive some of them, the record does not contain any waiver for others.

. Rule 11(c)(3) codified Boykin v. Alabama, 395 U.S. 238 , 89 S.Ct. 1709 , 23 L.Ed.2d 274 (1969), in which the Supreme Court held that a federal court may not infer from a silent record that the defendant had knowingly and intelligently waived certain of his constitutional rights. Id. at 243 , 89 S.Ct. at 1712. The Boykin Court emphasized three rights: the privilege against self-incrimination, the right to a juty trial, and the right to confront one’s accusers. Id.

. The government also argues that Gastelum had “stipulated’' that any "holes” in the Rule 11 proceeding could be "filled" by reference to the prior proceeding. We reject this argument. Upon reviewing the record, we conclude that Gastelum never agreed to waive any Rule 11 procedures. He simply wanted to preserve — for the use of his probation officer — certain findings of fact that were made during the prior proceeding about his remorsefulness. Had Gastelum actually “stipulated” to filling in the holes with the prior proceeding, the government would not have reminded the district court that it had failed to instruct Gastelum of his rights during the present proceedings.

. By way of example, the advisory committee offered three illustrations of harmless error in the Rule 11 context. First, "where the judge’s compliance with subdivision (c)(1) was not absolutely complete, in that some essential element of the crime was not mentioned, but the defendant’s responses clearly indicate his awareness of that element.” Second, "where the judge’s compliance with subdivision (c)(2) was erroneous in part in that the judge understated the maximum penalty somewhat, but the penalty actually imposed did not exceed that indicated in the warnings." Third, “where the judge completely failed to comply with subdivision (c)(5), which of course has no bearing on the validity of the plea itself.” Id.

. The government argues that the burden was on the defendant to "withdraw his plea,” to "indicate that he had changed his mind," or to "demonstrate that his plea was not knowing and voluntary.” We disagree. The plain language of Rule 11 places the burden on the court to determine that the defendant’s plea is knowing and voluntary before it accepts a guilty plea. See, e.g., Fed.R.Crim.Pro. 11(c) ("Before accepting a plea of guilty ..., the court must ... determine that the defendant understands, the following [rights]-").

. Because we vacate Gastelum’s plea on this ground, we need not reach his other claims.