Vodafone states it is making an effort to combat “disruption” to its mobile and fixed-line broadband services.
It has experienced a fault with a global link used to transmit data between countries yet is rerouting traffic to address the issue.
Reports on the DownDetector website indicate that subscribers in the UK, Ireland, Greece, Italy, Portugal and Germany are among those affected.
The problem seems to have begun after 14:00 BST. Some influenced users have, however, reported that problems with email and other internet-based activities have been resolved.
The fault comes a day after the firm declared that it had begun enabling users to link their accounts to Amazon’s Alexa service, enabling them to call contacts through the US company’s smart speakers. But, there is absolutely no suggestion that this was the cause of the outage.