Banks 'may launch joint RBS bid'

National Australia Bank and BBVA are among the frontrunners for the RBS portfolio, which is also in the sights of Santander, the Spanish bank that has bought Abbey, Alliance & Leicester and parts of Bradford & Bingley.

A joint venture could serve as a platform to acquire other British banks due to come up for sale, the Sunday Times said.

The RBS network, which comes with the Williams & Glyn's brand name, is being sold as part of the bank's penalty for accepting billions of pounds in state aid at the time of the credit crunch.

The European Commission has stipulated that accounts transferred as part of the sale must account for five per cent of the small business banking market. Santander is likely to be interested in building its presence in this area in the UK, particularly as its mortgage dominance will prevent it from bidding for Northern Rock or the parts of Lloyds Banking Group that are also due to be sold.

National Australia has around 2.7 million UK customers through Glasgow-based Clydesdale Bank, which incorporates the Yorkshire Bank brand. The business has a total of 340 branches, consisting of 188 Yorkshire Bank and 152 Clydesdale.

Group chief executive Cameron Clyne recently highlighted opportunities in the UK through acquisition or "joint arrangements with other parties".