diff --git a/rs/ledger_suite/icrc1/index-ng/index-ng.did b/rs/ledger_suite/icrc1/index-ng/index-ng.did
index 6947a961fe9a..f7e83c2e7c3f 100644
--- a/rs/ledger_suite/icrc1/index-ng/index-ng.did
+++ b/rs/ledger_suite/icrc1/index-ng/index-ng.did
@@ -61,12 +61,12 @@ type Transaction = record {
 };
 
 type Approve = record {
-  fee : opt nat;
+  fee : opt Tokens;
   from : Account;
   memo : opt vec nat8;
   created_at_time : opt nat64;
-  amount : nat;
-  expected_allowance : opt nat;
+  amount : Tokens;
+  expected_allowance : opt Tokens;
   expires_at : opt nat64;
   spender : Account;
 };
@@ -75,7 +75,7 @@ type Burn = record {
   from : Account;
   memo : opt vec nat8;
   created_at_time : opt nat64;
-  amount : nat;
+  amount : Tokens;
   spender : opt Account;
 };
 
@@ -83,16 +83,16 @@ type Mint = record {
   to : Account;
   memo : opt vec nat8;
   created_at_time : opt nat64;
-  amount : nat;
+  amount : Tokens;
 };
 
 type Transfer = record {
   to : Account;
-  fee : opt nat;
+  fee : opt Tokens;
   from : Account;
   memo : opt vec nat8;
   created_at_time : opt nat64;
-  amount : nat;
+  amount : Tokens;
   spender : opt Account;
 };