Millions of O2 customers have been unable to to make or receive calls or data since around Midday today.
The mobile phone company says it has now fixed the fault but that customers may still experience problems as full service returns.
More top news
President Michel Temer arrived in Chapeco to oversee the remaining repatriation of victims of the Colombia plane crash.
Most parts will be dry this afternoon, although there are a few showers out to the western fringes of Britain.
The Indonesian police plane dropped out of contact and villagers have 'found police uniforms' in the sea.