AWS SQS与PHP连接时无效令牌，但使用Python无效

Question

I'm having a very peculiar issue with trying to connect to AWS SQS. When running this PHP code:

$client = SqsClient::factory(array(
    'credentials' => [
       'key' => 'somekey',
       'secret' => 'somesecret'
    ],
    'region'  => 'eu-west-1',
    'version' => 'latest'
));
$result = $client->receiveMessage(array(
    'QueueUrl' => $queueUrl,
));

I'm getting this error:

PHP Fatal error:  Uncaught exception 'Aws\Sqs\Exception\SqsException' with message 'Error executing "ReceiveMess
age" on "https://sqs.eu-west-1.amazonaws.com/189729872213/my-very-special-queue"; AWS HTTP error: Client error: 403 Inva
lidClientTokenId (client): This account is suspended - <?xml version="1.0"?><ErrorResponse xmlns="http://queue.a
mazonaws.com/doc/2012-11-05/"><Error><Type>Sender</Type><Code>InvalidClientTokenId</Code><Message>This account i
s suspended</Message><Detail/></Error><RequestId>aaf63243-6840-5b49-893a-7d66919c07da</RequestId></ErrorResponse
>'

But when I'm using boto (the Python equivalent of AWS PHP SDK) with the same credentials on the same machine it works fine! And the account is opened as expected, and I can access all the queues that are associated with it.

How can I make the PHP code work? What should I be checking?