Entrepreneur Richard Branson has boosted his U.K. retail banking ambitions, announcing a tie-up with veteran U.S. investor Wilbur Ross that should give his business the firepower to bid for assets coming up for sale, including those of Royal Bank of Scotland Group PLC.

According to people familiar with the situation, Branson's Virgin Money, which on Tuesday confirmed that Ross has bought a 21% stake in the company for 100 million pounds ($152.3 million), planned to make an offer for 318 RBS branches by the end of Tuesday.

The Tuesday deadline for the first round of bids was expected to attract at least two other players — Banco Santander SA of Spain and National Australia Bank Ltd.

Spanish bank Banco Bilbao Vizcaya Argentaria SA and private-equity firms are also considering offers, people familiar with the situation have said. The price tag for the assets is estimated at between 1 billion pounds ($1.5 billion) and 2 billion pounds ($3 billion).

The branches in England and Wales, along with NatWest branches in Scotland and the accounts of other customers across the U.K., will allow the new owner to expand fast in a mature market that analysts say still has strong potential.

The U.K. banking sector was one of the hardest hit by the financial crisis, which led many banks to be partially or fully nationalized. RBS is now 84%-government owned, while peer Lloyds Banking Group PLC is 41% owned by the state. Northern Rock PLC was fully nationalized and a part of it will be put up for sale shortly.

In return for receiving the state aid, RBS, Lloyds and Northern Rock have been ordered by the European Commission to sell branches and other assets.

The U.K. government has said it expects the sale will attract new players in the market.

Virgin Money, which earlier this year entered the U.K. retail banking market by acquiring Church House Trust, will get 500 million pounds ($761 million) from Ross for asset bids, according to a person familiar with the situation.

Other new players entering the sector include Tesco PLC and U.S. entrepreneur Vernon Hill's Metro Bank, which received a banking license last month.

Both banks, however, are planning on growing organically and have said they will not be chasing the assets being put up for sale.

Subscribe Now

Access to authoritative analysis and perspective and our data-driven report series.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.