diff --git a/packages/crypto/src/bip39.ts b/packages/crypto/src/bip39.ts
index cb131861..433c819f 100644
--- a/packages/crypto/src/bip39.ts
+++ b/packages/crypto/src/bip39.ts
@@ -1,8 +1,5 @@
-import { fromHex, toHex, toUtf8 } from "@cosmjs/encoding";
+import { fromHex, toHex } from "@cosmjs/encoding";
 import * as bip39 from "bip39";
-import { pbkdf2 } from "pbkdf2";
-import * as unorm from "unorm";
-
 import { EnglishMnemonic } from "./englishmnemonic";
 
 export class Bip39 {
@@ -36,30 +33,6 @@ export class Bip39 {
   }
 
   public static async mnemonicToSeed(mnemonic: EnglishMnemonic, password?: string): Promise<Uint8Array> {
-    // reimplementation of bip39.mnemonicToSeed using the asynchronous
-    // interface of https://www.npmjs.com/package/pbkdf2
-    const mnemonicBytes = toUtf8(unorm.nfkd(mnemonic.toString()));
-    const salt = "mnemonic" + (password ? unorm.nfkd(password) : "");
-    const saltBytes = toUtf8(salt);
-    return this.pbkdf2(mnemonicBytes, saltBytes, 2048, 64, "sha512");
-  }
-
-  // convert pbkdf2's callback interface to Promise interface
-  private static async pbkdf2(
-    secret: Uint8Array,
-    salt: Uint8Array,
-    iterations: number,
-    keylen: number,
-    digest: string,
-  ): Promise<Uint8Array> {
-    return new Promise<any>((resolve, reject) => {
-      pbkdf2(secret, salt, iterations, keylen, digest, (err, derivedKey) => {
-        if (err) {
-          reject(err);
-        } else {
-          resolve(new Uint8Array(derivedKey));
-        }
-      });
-    });
+    return new Uint8Array(await bip39.mnemonicToSeed(mnemonic.toString(), password));
   }
 }