Northern Rock has borrowed a further £5 billion from the Bank of England, a report claimed today.
The troubled lender now owes close to £8 billion to the central bank, the Financial Times claimed, without citing sources.
Rumours that Northern Rock has asked the Bank of England to loan it more cash comes after it was granted emergency funds from the institution almost two weeks ago.
According to the FT, the Newcastle-based bank has now borrowed the equivalent of a third of its retail deposits at the end of June, with the paper claiming that news of a fresh loan will raise additional concerns about its financial health.
Shares in Northern Rock lifted slightly yesterday, amid hopes that a white knight buyer could emerge to secure the long-term future of the bank.
In a statement earlier this week the beleaguered lender confirmed that it is in "preliminary discussions with selected parties" over its future.
Northern Rock revealed that it had "received a number of approaches regarding a variety of potential transactions, including the possibility of an offer being made for the company".
It is reported that Spanish entrepreneur Jose Maria Ruiz-Mateos, who made his fortune marketing the sherry Harveys of Bristol, is among those interested in Northern Rock.
But the FT said today that creditors holding the bank's tier two debt were establishing a formal committee to protect their interests in the event of any restructuring or insolvency.
Northern Rock has yet to comment on the claims.
This week the bank also confirmed that it no longer plans to pay its shareholders a 14.2p a share dividend this year.
Analysts had warned that the planned £59 million payout to Northern Rock investors would have proved controversial in the wake of the government's pledge to guarantee all existing deposits held with the bank.
Chancellor Alistair Darling announced the move after savers rushed to withdraw their cash from the company when it was revealed earlier this month that Northern Rock had asked the Bank of England to act as a lender of last resort. The lender made the request as a result of the difficulties that banks have been facing in securing funding in the wake of a global credit crunch.