Potential suitors of Northern Rock (NRK) must submit their proposals today to rescue the bank.

Virgin Group and US private equity firms JC Flowers and Cerberus are among those expected to come forward with rescue bids for the troubled lender.

Any future owner will have to pay back about £24 billion of Bank of England loans.

New York-based private equity firm JC Flowers has put together a management team led by former Marks & Spencer chairman Paul Myners if talks lead to a successful offer. It has also proposed to install former Alliance & Leicester boss Richard Pym as the bank's interim CEO.

Virgin Money has the support of insurance giant AIG, and American investor Wilbur Ross who is a specialist in turning around failed companies. Its consortium is made up with hedge fund Toscafund and Hong Kong-based First Eastern Investment.

It is understood to be preparing a £1.5 billion equity injection to salvage the group, which would be renamed Virgin Money.

Virgin Group boss Richard Branson said he wished to retain the Newcastle-based lender 'in its entirety' and grow the business rather than seeking a break-up of the group.

US private equity firm Cerberus is keen to buy Northern Rock's mortgage assets at a discount and a likely player in any break-up of the group. Reports suggest US financial services firm GMAC may play a key role in the Cerberus bid.

Ex-CEO of banking groups UBS and Abbey, Luqman Arnold, is also in the picture. He wants to rescue the business rather than table a bid.

His vehicle, Olivant, would take a minority 15% stake in Northern Rock - worth around £85 million - and make a return through a recovering share price.

Shares in Northern Rock slipped 1.5% to 132.7p in anticipation of the bids on Friday.