Customer numbers surged over Christmas

The rise means the firm's subscriber base has risen to 20.1 million.

MM02 added that the average revenues per customer were robust, climbing �5 to �264 in the UK over the past year.

"Following this strong... performance, all our businesses remain on track to deliver our full-year growth and margin targets," the company said.

The group added that text message volumes grew by 12.2% to 2.89bn over the three months to the end of December.

MM02 is currently ranked fourth in terms of customer numbers behind rivals Vodafone, Orange and T-Mobile.

Future challenges

The news comes in the wake of strong new user numbers from rivals T-Mobile and Virgin last week.

But despite the firm's confidence for the future, experts warned there could be challenges ahead.

Competition in the UK is set to hot up with 3 UK, a mobile phone operator controlled by Hong Kong's Hutchison Whampoa, poised to launch its first -- albeit delayed -- pre-paid service.

Shares in MM02 have proved vulnerable to news of cut-price tariffs from 3 UK, as the UK-based group depends more on its domestic market for revenues than its larger rivals do.

German markets could also prove to be tough, as larger rivals are currently slashing prices.