Stricken British bank Northern Rock (NRK.L) has received more rescue proposals, but warned that one of them contemplated an offer well below Tuesday's closing price, sparking a new slide in its shares on Wednesday.

The mortgage lender declined to disclose the number or names of its suitors.

Northern Rock was forced to go to the Bank of England for emergency loans two months ago, as the global squeeze on credit caused its funding strategy to collapse, prompting the first run on a British bank since the 19th century.

It shares have since plunged and its borrowing from the Bank of England is estimated to have reached 25 billion pounds ($52 billion) as the authorities desperately cast around for a buyer.

A consortium led by Richard Branson's Virgin Group (VA.UL) and Olivant, an investment group led by veteran troubleshooter Luqman Arnold, said on Friday they had submitted proposals for Northern Rock.

People familiar with the situation told Reuters on Tuesday that U.S. buyout firms JC Flowers and Cerberus had also made proposals, and the one from JC Flowers included an offer to Northern Rock shareholders at a nominal value.

At 3:10 a.m. EST, Northern Rock shares were down 13.6 percent at 87.9 pence, though off Tuesday's record low of 60 pence, valuing the business at about 370 million pounds.

The company has received additional indicative expressions of interest covering a range of options for the business, one of which does contemplate an offer for the company materially below the market price at the close of business on Tuesday, Northern Rock said in a statement.

The company's advisors have begun discussions with a number of selected interested parties to clarify their proposals.

U.S. buyout firm Apollo and Dutch bank ING (ING.AS) have also been tipped as potential bidders for Northern Rock.