O2 are reporting a network outage which means they cannot make calls or browse the web.

The issues also affect Tesco Mobile customers whose service runs on the O2 network.

O2 have said there is a voice issue "that may be affecting some customers" and that its technical teams are investigating.

It said: "We apologise for any inconvenience."

Issues which began around lunchtime on Wednesday with thousands of issues logged by customers of O2 and Tesco Mobile on the outage detection site Down Detector.

The areas with the most reported issues include Glasgow, London, Manchester, Bristol, Leeds, Belfast, Nottingham, Birmingham and Leicester.

Around Lenzie, in East Dunbartonshire, O2 reported that a nearby phone mast was not working. The telecoms provider said their engineers will already be on the case and that service "might come and go" until we fix it.

The Herald:

Both the O2 and Tesco Mobile social media channels are being hit by concerned customers alerting them to issues.

Among those complaining was the owner of Ellie's Craft House on the Isle of Lewis, who said: "I can’t make or receive calls - I’m in HS2 area, Isle of Lewis. Your service Status says there’s a local mast issue which cannot be correct as there’s reports all over the UK about the service being down. The least you could do is report what is actually happening!"

Another complainer, Lewis Williams said: "Fuming with Tesco Mobile. Can't make phone calls, or receive them?? This is my only point of contact and I dread to think if something happened to my kids at school and I can’t be contacted. Fix this issue immediately please or contact me to at least let me know the situation."

Tesco Mobile responded saying: "We're aware of a calling issue that's impacting a small number of customers. Our technical teams are investigating. We're sorry for any inconvenience caused."

O2 said that only a "very small" number of customers were reporting issues "out of a customer base of many millions".  O2 have been asked what that "very small" number is but have been unable to respond.

An O2 spokesperson said: “Our mobile network is working and customers can make calls and use their data. We’re aware that a very small number of customers are reporting issues and we are investigating this.”

Tesco Mobile later advised customers affected to restart their phones periodically adding: "Once the issue is resolved your phone will connect back to the network fully."