diff --git a/backend/src/services/identity-aws-auth/identity-aws-auth-fns.ts b/backend/src/services/identity-aws-auth/identity-aws-auth-fns.ts
index 38944917e..a028bc25f 100644
--- a/backend/src/services/identity-aws-auth/identity-aws-auth-fns.ts
+++ b/backend/src/services/identity-aws-auth/identity-aws-auth-fns.ts
@@ -83,9 +83,11 @@ export const extractPrincipalArnEntity = (arn: string, formatAsIamRole: boolean
  * Extracts the identity ARN from the GetCallerIdentity response to one of the following formats:
  * - arn:aws:iam::123456789012:user/MyUserName
  * - arn:aws:iam::123456789012:role/MyRoleName
+ * - arn:aws-us-gov:iam::123456789012:user/MyUserName (GovCloud)
+ * - arn:aws-us-gov:iam::123456789012:role/MyRoleName (GovCloud)
  */
 export const extractPrincipalArn = (arn: string, formatAsIamRole: boolean = false) => {
   const entity = extractPrincipalArnEntity(arn, formatAsIamRole);
 
-  return `arn:aws:${formatAsIamRole ? "iam" : entity.Service}::${entity.AccountNumber}:${entity.Type}/${entity.FriendlyName}`;
+  return `arn:${entity.Partition}:${formatAsIamRole ? "iam" : entity.Service}::${entity.AccountNumber}:${entity.Type}/${entity.FriendlyName}`;
 };
diff --git a/backend/src/services/identity-aws-auth/identity-aws-auth-validators.ts b/backend/src/services/identity-aws-auth/identity-aws-auth-validators.ts
index 4e3884e15..ed7f6696a 100644
--- a/backend/src/services/identity-aws-auth/identity-aws-auth-validators.ts
+++ b/backend/src/services/identity-aws-auth/identity-aws-auth-validators.ts
@@ -6,7 +6,7 @@ const twelveDigitRegex = new RE2(/^\d{12}$/);
 // akhilmhdh: change this to a normal function later. Checked no redosable at the moment
 
 const arnRegex = new RE2(
-  /^arn:aws:(iam|sts)::\d{12}:(user\/[a-zA-Z0-9_.@+*/-]+|role\/[a-zA-Z0-9_.@+*/-]+|assumed-role\/[a-zA-Z0-9_.@+*/-]+|\*)$/
+  /^arn:aws(?:-us-gov)?:(iam|sts)::\d{12}:(user\/[a-zA-Z0-9_.@+*/-]+|role\/[a-zA-Z0-9_.@+*/-]+|assumed-role\/[a-zA-Z0-9_.@+*/-]+|\*)$/
 );
 
 export const validateAccountIds = z
@@ -55,7 +55,7 @@ export const validatePrincipalArns = z
     },
     {
       message:
-        "Each ARN must be in the format of 'arn:aws:iam::123456789012:user/UserName', 'arn:aws:iam::123456789012:role/RoleName', or 'arn:aws:iam::123456789012:*', 'arn:aws:sts::123456789012:assumed-role/RoleName'."
+        "Each ARN must be in the format of 'arn:aws:iam::123456789012:user/UserName', 'arn:aws:iam::123456789012:role/RoleName', or 'arn:aws:iam::123456789012:*', 'arn:aws:sts::123456789012:assumed-role/RoleName'. GovCloud ARNs (arn:aws-us-gov:...) are also supported."
     }
   )
   // Transform to normalize the spaces around commas