O2's problems are seemingly worldwide, and the network have confirmed they are hard at work solving the current issues.
It doesn't end there, because some major MVNO (virtual networks) that piggyback O2 signals are experiencing the same disruption.
The spokesperson added: "Voice calls are working OK".
In a tweet, the network said that the issue lay with one of its third-party suppliers, and recommended that users switch to Wi-Fi wherever possible.
In an online statement, O2 said: "We are aware our customers are unable to use data this morning. My teams are working really hard with Ericsson to find a swift resolution".
O2, Britain's second biggest network, and Japan's Softbank reported network outages on Thursday, leaving many customers unable to access internet services.
I want to let our customers know how sorry I am for the impact our network data issue has had on them, and reassure them that our teams, together with Ericsson, are doing everything we can.
In total, around 32 million customers are affected.
"After the incident, SoftBank received a report from Ericsson that the software has been in operation since nine months ago and the failure caused by the same software also occurred simultaneously in other telecom carriers across 11 countries, which installed the same Ericsson-made devices".
The Swedish equipment maker, which manufactures much of the backend gear in the world's cellular networks, said today the outage was down to an expired certificate in an earlier version of its management software that was in use by a number of European telcos.
Connected vehicles have also been affected, and the issue (obviously) also affects mobile virtual network operators (MVNOs) that use the O2 network.