diff --git a/lithops/serverless/backends/aws_lambda/aws_lambda.py b/lithops/serverless/backends/aws_lambda/aws_lambda.py
index d44173de7..337ad14ff 100644
--- a/lithops/serverless/backends/aws_lambda/aws_lambda.py
+++ b/lithops/serverless/backends/aws_lambda/aws_lambda.py
@@ -64,8 +64,8 @@ def __init__(self, lambda_config, internal_storage):
         logger.debug('Creating Boto3 AWS Session and Lambda Client')
 
         self.aws_session = boto3.Session(
-            aws_access_key_id=lambda_config['access_key_id'],
-            aws_secret_access_key=lambda_config['secret_access_key'],
+            aws_access_key_id=lambda_config.get('access_key_id'),
+            aws_secret_access_key=lambda_config.get('secret_access_key'),
             aws_session_token=lambda_config.get('session_token'),
             region_name=self.region_name
         )
diff --git a/lithops/serverless/backends/aws_lambda/config.py b/lithops/serverless/backends/aws_lambda/config.py
index 68027e6f6..78ad143b4 100644
--- a/lithops/serverless/backends/aws_lambda/config.py
+++ b/lithops/serverless/backends/aws_lambda/config.py
@@ -70,9 +70,6 @@ def load_config(config_data):
     if 'aws' not in config_data:
         raise Exception("'aws' section is mandatory in the configuration")
 
-    if not {'access_key_id', 'secret_access_key'}.issubset(set(config_data['aws'])):
-        raise Exception("'access_key_id' and 'secret_access_key' are mandatory under the 'aws' section of the configuration")
-
     if not config_data['aws_lambda']:
         raise Exception("'aws_lambda' section is mandatory in the configuration")
 
diff --git a/lithops/storage/backends/aws_s3/aws_s3.py b/lithops/storage/backends/aws_s3/aws_s3.py
index 0955b2dc3..70ee263a7 100644
--- a/lithops/storage/backends/aws_s3/aws_s3.py
+++ b/lithops/storage/backends/aws_s3/aws_s3.py
@@ -42,27 +42,20 @@ def __init__(self, s3_config):
         self.secret_access_key = s3_config.get('secret_access_key')
         self.session_token = s3_config.get('session_token')
 
-        if self.access_key_id and self.secret_access_key:
-            client_config = Config(
-                max_pool_connections=128,
-                user_agent_extra=self.user_agent,
-                connect_timeout=CONN_READ_TIMEOUT,
-                read_timeout=CONN_READ_TIMEOUT,
-                retries={'max_attempts': OBJ_REQ_RETRIES}
-            )
-            self.s3_client = boto3.client(
-                's3', aws_access_key_id=self.access_key_id,
-                aws_secret_access_key=self.secret_access_key,
-                aws_session_token=self.session_token,
-                config=client_config,
-                region_name=self.region_name
-            )
-        else:
-            client_config = Config(
-                signature_version=UNSIGNED,
-                user_agent_extra=self.user_agent
-            )
-            self.s3_client = boto3.client('s3', config=client_config)
+        client_config = Config(
+            max_pool_connections=128,
+            user_agent_extra=self.user_agent,
+            connect_timeout=CONN_READ_TIMEOUT,
+            read_timeout=CONN_READ_TIMEOUT,
+            retries={'max_attempts': OBJ_REQ_RETRIES}
+        )
+        self.s3_client = boto3.client(
+            's3', aws_access_key_id=self.access_key_id,
+            aws_secret_access_key=self.secret_access_key,
+            aws_session_token=self.session_token,
+            config=client_config,
+            region_name=self.region_name
+        )
 
         msg = STORAGE_CLI_MSG.format('S3')
         logger.info(f"{msg} - Region: {self.region_name}")
diff --git a/lithops/storage/backends/aws_s3/config.py b/lithops/storage/backends/aws_s3/config.py
index 60585a827..afea64007 100644
--- a/lithops/storage/backends/aws_s3/config.py
+++ b/lithops/storage/backends/aws_s3/config.py
@@ -22,9 +22,6 @@ def load_config(config_data):
 
     if 'aws' in config_data:
 
-        if not {'access_key_id', 'secret_access_key'}.issubset(set(config_data['aws'])):
-            raise Exception("'access_key_id' and 'secret_access_key' are mandatory under the 'aws' section of the configuration")
-
         if 'aws_s3' not in config_data:
             config_data['aws_s3'] = {}