Mr Branson is hoping to capitalise on his airline to attract transatlantic business customers to the new venture. Mobile phones which function in both the UK and the US will be available at Virgin Atlantic outlets.
At present, most domestic business travellers to the US have to hire special phones to make calls back to the UK.
The launch of the venture has been delayed by the protracted sale of One2One by its owners, Britain's Cable & Wireless and MediaOne of America. However, on Friday, Deutsche Telekom announced the pounds 8.4bn acquisition of One2One, enabling final preparations to be made for the unveiling of Virgin Mobile.
The new operation will be headed by Tom Alexander, formerly of Cellnet.
As well as using Virgin Atlantic, Virgin Mobile will sell phones over the internet and telephone, and in other Virgin retail outlets.
The products are intended to be available in time for the lucrative Christmas market, when the bulk of mobile phones are sold.
The launch has been a bonanza for Trowbridge, the Wiltshire town where Virgin Mobile is basing its call centre to handle inquiries. There have already been 5,500 applications for the 400 jobs available. Selling the phones direct from the call centre will cut out the commission paid to high-street shops like Carphone Warehouse, the same trick that Virgin's financial services arm has used to great effect.
Virgin Mobile is also aiming to be in the vanguard of mobile phone operators offering models that are compatible with e-commerce. For health reasons, it is also planning to offer hands-free headsets with all its phones.