[BUG] AWS Bedrock, Calling us-east-2 region instead of the specified region

Environment

• Platform (select one):
• [ ] Anthropic API
• [x] AWS Bedrock
• [ ] Google Vertex AI
• [ ] Other: <!-- specify -->
• Claude CLI version: 0.2.49 (Claude Code)
• Operating System: macOS 15.2
• Terminal: iTerm2

Using AWS Control Tower to restrict access to regions other than us-east-1 and ap-northeast-1
Sonnet 3.7 and Haiku 3.5 are available in us-east-1

Bug Description

Regardless of the region specified in AWS environment variables or profiles, Claude Code uses models in the us-east-2 region.

Steps to Reproduce

1. Block access to us-east-2
2. Request access to Claude Sonnet 3.7 and Haiku 3.5 in us-east-1
3. Create an IAM user with the AmazonBedrockFullAccess policy
4. Create a profile for the IAM user with default region us-east-1
5. Run claude with the environment variables set
6. When making any request, a 403 error occurs

Expected Behavior

Claude Code should use models in us-east-1 and execute normally.

Actual Behavior

> test
  ⎿  API Error: 403 {"Message":"User: arn:aws:iam::160885266706:user/test-claude-code-20250319 is not authorized to perform: bedrock:InvokeModelWithResponseStream on

Additional Context

Environment Variables

export AWS_PROFILE={iam-user-profile-name}
export CLAUDE_CODE_USE_BEDROCK=1
export ANTHROPIC_MODEL='us.anthropic.claude-3-7-sonnet-20250219-v1:0'
export ANTHROPIC_SMALL_FAST_MODEL='us.anthropic.claude-3-5-haiku-20241022-v1:0'
export DISABLE_PROMPT_CACHING=1

Error message from AWS CloudTrail event record:

User: arn:aws:iam::XXXXXXXXXX:user/XXXXXXXXXX is not authorized to perform: bedrock:InvokeModelWithResponseStream on resource: arn:aws:bedrock:us-east-2::foundation-model/anthropic.claude-3-5-haiku-20241022-v1:0 with an explicit deny in a service control policy"