diff --git a/lib/rag-engines/data-import/functions/upload-handler/index.py b/lib/rag-engines/data-import/functions/upload-handler/index.py
index 1238e1caa..f54c78bb6 100644
--- a/lib/rag-engines/data-import/functions/upload-handler/index.py
+++ b/lib/rag-engines/data-import/functions/upload-handler/index.py
@@ -7,12 +7,13 @@
 from aws_lambda_powertools import Logger, Tracer
 from aws_lambda_powertools.utilities.data_classes import SQSEvent, event_source
 from aws_lambda_powertools.utilities.typing import LambdaContext
+from botocore.config import Config
 
 logger = Logger()
 tracer = Tracer()
 
 sfn_client = boto3.client("stepfunctions")
-s3 = boto3.client("s3")
+s3 = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 
 FILE_IMPORT_WORKFLOW_ARN = os.environ.get("FILE_IMPORT_WORKFLOW_ARN")
 PROCESSING_BUCKET_NAME = os.environ.get("PROCESSING_BUCKET_NAME")
diff --git a/lib/sagemaker-model/hf-custom-script-model/build-script/script.py b/lib/sagemaker-model/hf-custom-script-model/build-script/script.py
index 819c3d4cd..768f4bc98 100644
--- a/lib/sagemaker-model/hf-custom-script-model/build-script/script.py
+++ b/lib/sagemaker-model/hf-custom-script-model/build-script/script.py
@@ -7,9 +7,10 @@
 from pathlib import Path
 
 import boto3
+from botocore.config import Config
 from huggingface_hub import snapshot_download
 
-s3_client = boto3.client("s3")
+s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 
 local_model_folder = os.getenv("LOCAL_MODEL_FOLDER", "./model")
 bucket = os.getenv("BUILD_BUCKET", "")
diff --git a/lib/shared/file-import-batch-job/main.py b/lib/shared/file-import-batch-job/main.py
index 9255976a5..d92bb5cfb 100644
--- a/lib/shared/file-import-batch-job/main.py
+++ b/lib/shared/file-import-batch-job/main.py
@@ -1,5 +1,6 @@
 import os
 import boto3
+from botocore.config import Config
 import genai_core.types
 import genai_core.chunks
 import genai_core.documents
@@ -14,7 +15,7 @@
 PROCESSING_BUCKET_NAME = os.environ.get("PROCESSING_BUCKET_NAME")
 PROCESSING_OBJECT_KEY = os.environ.get("PROCESSING_OBJECT_KEY")
 
-s3_client = boto3.client("s3")
+s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 
 
 def main():
diff --git a/lib/shared/layers/python-sdk/python/genai_core/documents.py b/lib/shared/layers/python-sdk/python/genai_core/documents.py
index 81e8d679b..0ad6daafe 100644
--- a/lib/shared/layers/python-sdk/python/genai_core/documents.py
+++ b/lib/shared/layers/python-sdk/python/genai_core/documents.py
@@ -3,6 +3,7 @@
 import uuid
 from aws_lambda_powertools import Logger
 import boto3
+from botocore.config import Config
 import botocore
 import feedparser
 import genai_core.types
@@ -35,7 +36,7 @@
 WORKSPACE_OBJECT_TYPE = "workspace"
 
 s3 = boto3.resource("s3")
-s3_client = boto3.client("s3")
+s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 dynamodb = boto3.resource("dynamodb")
 dynamodb_client = boto3.client("dynamodb")
 sfn_client = boto3.client("stepfunctions")
diff --git a/lib/shared/layers/python-sdk/python/genai_core/presign.py b/lib/shared/layers/python-sdk/python/genai_core/presign.py
index 8930f5d17..4614bef92 100644
--- a/lib/shared/layers/python-sdk/python/genai_core/presign.py
+++ b/lib/shared/layers/python-sdk/python/genai_core/presign.py
@@ -12,6 +12,7 @@
 
 s3_client = boto3.client(
     "s3",
+    region_name = os.environ['AWS_REGION'],
     config=botocore.config.Config(
         # Presign URLs only work with CMK if sigv4 is used
         # (boto3 default to v2 in some cases)
diff --git a/lib/shared/layers/python-sdk/python/genai_core/user_feedback.py b/lib/shared/layers/python-sdk/python/genai_core/user_feedback.py
index 99cf4dfa4..6f90d0c47 100644
--- a/lib/shared/layers/python-sdk/python/genai_core/user_feedback.py
+++ b/lib/shared/layers/python-sdk/python/genai_core/user_feedback.py
@@ -2,11 +2,12 @@
 import uuid
 from aws_lambda_powertools import Logger
 import boto3
+from botocore.config import Config
 import json
 from datetime import datetime
 
 dynamodb = boto3.resource("dynamodb")
-s3_client = boto3.client("s3")
+s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 logger = Logger()
 
 USER_FEEDBACK_BUCKET_NAME = os.environ.get("USER_FEEDBACK_BUCKET_NAME")
diff --git a/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_object_key.py b/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_object_key.py
index e5dffcb0d..edad27cd3 100644
--- a/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_object_key.py
+++ b/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_object_key.py
@@ -1,10 +1,12 @@
 from aws_lambda_powertools import Logger
 import boto3
+from botocore.config import Config
+import os
 
 logger = Logger()
 
 
 def delete_files_with_object_key(bucket_name, object_key):
-    s3_client = boto3.client("s3")
+    s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
     s3_client.delete_object(Bucket=bucket_name, Key=object_key)
     logger.info(f"Deleted {object_key} from {bucket_name}.")
diff --git a/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_prefix.py b/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_prefix.py
index 53115fb76..098e14f34 100644
--- a/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_prefix.py
+++ b/lib/shared/layers/python-sdk/python/genai_core/utils/delete_files_with_prefix.py
@@ -1,11 +1,13 @@
 from aws_lambda_powertools import Logger
 import boto3
+from botocore.config import Config
+import os
 
 logger = Logger()
 
 
 def delete_files_with_prefix(bucket_name, prefix):
-    s3_client = boto3.client("s3")
+    s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
     continuation_token = None
 
     while True:
diff --git a/lib/shared/layers/python-sdk/python/genai_core/utils/files.py b/lib/shared/layers/python-sdk/python/genai_core/utils/files.py
index 7abaaeb26..f9c276921 100644
--- a/lib/shared/layers/python-sdk/python/genai_core/utils/files.py
+++ b/lib/shared/layers/python-sdk/python/genai_core/utils/files.py
@@ -1,6 +1,8 @@
 import boto3
+from botocore.config import Config
+import os
 
-s3 = boto3.client("s3")
+s3 = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 
 
 def file_exists(bucket, key):
diff --git a/lib/shared/web-crawler-batch-job/index.py b/lib/shared/web-crawler-batch-job/index.py
index a7a6d91dd..fefbad905 100644
--- a/lib/shared/web-crawler-batch-job/index.py
+++ b/lib/shared/web-crawler-batch-job/index.py
@@ -1,6 +1,7 @@
 import os
 import json
 import boto3
+from botocore.config import Config
 import genai_core.utils.json
 import genai_core.websites.crawler
 
@@ -8,7 +9,7 @@
 WORKSPACE_ID = os.environ["WORKSPACE_ID"]
 DOCUMENT_ID = os.environ["DOCUMENT_ID"]
 OBJECT_KEY = os.environ["INPUT_OBJECT_KEY"]
-s3_client = boto3.client("s3")
+s3_client = boto3.client("s3", region_name = os.environ['AWS_REGION'], config = Config(signature_version = 's3v4'))
 
 
 def main():