Intense turmoil in the financial markets precipitated by Lehman Brothers’ collapse will pile pressure on retailers’ finances, bankers have warned.

Panic-stricken lenders are likely to impose tougher terms on store groups, who have borne the brunt of the consumer recession.

One banking source said: “Every bank is trying to repair ravaged balance sheets. The size and availability [of debt] is going to be questioned and where there are any question marks you’ll discover you can’t get credit.”

He said credit insurance would be harder to obtain. The changing landscape was confirmed when Woolworths reported that “deterioration in the credit insurance market may increase the group’s working capital requirements”.

Store groups have also had to contend with the travails of the world’s biggest insurer AIG, which was rescued on Tuesday by the US Federal Reserve. AIG underwrites warranties on some goods bought from John Lewis and sells insurance through Argos.

A John Lewis spokeswoman said it had replaced AIG in June and the insurer only underwrites a small proportion of free warranties.

On Wednesday HBOS, whose future has been the focus of intense speculation, revealed merger plans with Lloyds TSB. Sainsbury’s Bank is a joint venture with HBOS. No comment was available from Sainsbury’s on any implications.