UBS is considering legal action against executives who were paid massive sums at the height of the credit boom, to force them to relinquish some of their bonuses.

The bank, which has written off about $48bn in the credit crisis, said on Wednesday that it would discuss remuneration and ways of making staff more accountable for long-term performance at a special shareholders' meeting on November 27.

The meeting had initially been seen purely as a formality to approve the creation of new capital under a SFr6bn ($5.2bn) bailout agreed with the Swiss government last month.

But the agenda, sent to shareholders yesterday, includes discussion of a board report on compensation. While the first two points concern reviewing the existing system and proposed changes, item three involves the "issue of repayment of previously granted incentive awards".

UBS is the first big bank hit by the crisis to consider such clawbacks. As the financial markets turmoil has unfolded, many banks have been criticised for allowing huge payments to key staff without adequately considering the long-term earnings implications of what seemed initially profitable decisions.

But as the crisis has deepened, banks have suffered a backlash from investors and, latterly, governments, about payment practices. The outcry has focused particularly on groups, now including UBS, that have sought state aid.

Swiss experts doubted that UBS could successfully demand repayments, and suggested that the move might be an attempt to deflect public criticism.

"I can hardly imagine repayments could be enforced, unless the money has not yet been disbursed and the contractual language is so vague as to allow that", said Urs Lustenberger of Lustenberger, Glaus & Partner, a Zurich law firm.

"There were, in connection with the Swissair collapse, some directors who voluntarily repaid certain bonus payments. But there is no mechanism, as far as I know, to oblige such repayments", said Thomas Geiser, professor of labour law at the University of St Gallen.

"Also, I can't see how, under Swiss law, you could make such a demand legally binding", he added

Attention in Switzerland has focused on Marcel Ospel (left), UBS's former chairman, and the man identified with its breakneck growth into US investment banking.

Mr Ospel's annual package of SFr20m and more made him one of the best paid executives in the country and was a matter of public debate even before the credit crisis.

Criticism has also been levelled at last year's large severance payments to Peter Wuffli, Clive Standish and Huw Jenkins, the bank's former chief executive, chief financial officer and head of investment banking, respectively.

UBS's accounts show the three men received between them SFr60.6m after quitting their jobs, based on entitlements under their individual contracts.

UBS said it was also looking at ways to encourage voluntary repayments, as well as mechanisms that would allow shareholders more say on salaries and bonuses.

The bank is expected to set out its views on November 14 to give shareholders time to consider their positions before the special meeting.