The sale of media publisher Reed Business Information appeared uncertain on Tuesday amid difficulty in financing the deal.

The RBI sale, one of the few live auctions in the media sector worldwide, is a bellwether for the ability of companies to dispose of assets and of the capacity of private equity firms to complete deals in these credit market conditions.

Reed Elsevier originally offered so-called "staple" finance of $1.26bn (£685m) in three separate packages and on slightly different terms, from a consortium of seven banks led by UBS.

Staple financing is a pre-arranged package offered to potential bidders in an acquisition. The financing is arranged by the investment bank advising the selling company.

Two banks are questioning their ability to lend, according to people familiar with the situation. The lending banks include BNP Paribas, JPMorgan, Lloyds and Calyon.

Turmoil in the credit markets and uncertainty among lenders have left a shortfall of between 10 and 15 per cent of the total staple package, or up to $180m.

"A deal simply cannot be financed in these conditions. The staple financing is brittle," said one source familiar with the deal.

In order to complete the deal, the remaining lending banks would have to agree to put in more money, according to one person familiar with the situation. Alternatively, Reed may reach into its pockets to plug the gap. Reed declined to comment.

RBI has been valued at between £1bn and £1.25bn but bid interest is at the lower end of this estimate. Crispin Davis, chief executive of Reed Elsevier who retires next year, sees the sale of RBI as part of his legacy.

"The jury is still out. It isn't over yet. It is possible that a deal could be announced this year but [one] which didn't actually close until the following year so that details can be fine-tuned," said someone familiar with the deal.

There are three bidders remaining at the third round of bidding: Bain Capital, TPG and Strauss Zelnick, the former non-executive director of Reed Elsevier who has teamed up with private equity group Apollo.

The deadline for third round bids is in about three or four weeks.

Tobacco company Altria Group said last week it might postpone its acquisition of smokeless tobacco maker UST until January on advice of its lenders.

Altria said its lenders Goldman Sachs and JPMorgan Chase asked it to wait until next year in order to try to raise the funds to complete the deal.