Up to half a dozen expressions of interest are likely to emerge by tonight's deadline in connection with the sale of a portfolio of branches in Scotland and England that Royal Bank of Scotland must sell in line with an EU order.British weekend newspapers cite three more or less definite bidders and three probables. The first trio are National Australia Bank (with or without a private equity partner), Virgin Money (with co-investment from US investor Wilbur Ross) and Santander.The second three are BBVA, Credit Agricole and Handelsbanken. There is also talk in one newspaper of a bid from JC Flowers, the private equity firm.The twist over the weekend is the emergence of Wilbur Ross as a co-investor both in Virgin Money directly (which is seeking additional investors to hold up to one quarter of the firm) as well as the planned investment by Ross alongside Virgin Money to support the bid for the RBS branches.How seriously NAB regards this opportunity to add to its existing business trading in Britain as Clydesdale and Yorkshire banks is unclear. RBS is selling RBS branches along with 1.8 million retail customer relationships, 230,000 small business customers, and 1200 smaller corporate customers.The consensus in British reports regarding the value of this portfolio ranges from £1.5 billion to £2 billion, with outlying values put at twice or even more than this.A degree of additional competition is supposed to be emerging in banking in Britain, with Virgin Money resolved to develop a branch network if it cannot buy the RBS branches. Tesco and Metrobank (funded by private equity) are also talking up their expansion plans.