Virgin Mobile, the mobile phone arm of Sir Richard Branson's business empire, today confirmed plans for a stock market flotation in a move thought to value the company at more than £1 billion.

The market listing, which should be completed by the end of July, comes more than four years after the mobile phone arm of Virgin Group was set up.

Employees with the company for more than a year stand to benefit as they will be offered free shares expected to be worth hundreds of pounds.

The operation employs 1,400 staff at three sites - Trowbridge, London and Daventry - and has acquired around 4.1 million customers.

Full details of the float have not been disclosed, although it is expected that just under half of the group's shares will be sold on the market.

The move - still subject to market conditions - follows the flotation of Australian discount airline Virgin Blue last year.

Proceeds from the move - expected to be the biggest flotation so far this year - are likely to be used to fund Sir Richard's other business plans.

Sir Richard said: "In less than five years Virgin Mobile has grown from scratch to acquire more than 4 million customers.

"I am very proud of what the team has achieved so far and am confident that Virgin Mobile will go from strength to strength."

As a virtual operator, Virgin Mobile uses T-Mobile's network, which sold its 50 per cent stake in the UK's fifth largest mobile company to Virgin Group in January.

Sir Richard is expected to become the honorary president of the business, with Charles Gurassa, the former British Airways executive, appointed chairman.

Hilary Cook, of Barclays Stockbrokers, said Virgin Mobile's intention to float represented good news for the London market.

She added: "The fact that there is an appetite for new issues shows a sign of new confidence in the stock market."

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