No successor has yet been lined up to follow UBS chief executive Oswald Gruebel, the chairman of the Swiss bank's executive board was quoted as saying in a newspaper interview on Saturday.

Kaspar Villiger told the Neue Zuercher Zeitung that there was no mandatory retirement age but that provisions for an emergency had been made at UBS , which was bailed out by the Swiss government and stood accused of helping rich Americans dodge taxes in the U.S. tax investigation.

CEO Oswald Gruebel, a German born in 1943, was appointed at the end of February 2009 to turn around the beleaguered bank, which in 2008 made a net loss of 20.9 billion francs, Switzerland's annual biggest corporate loss.

Oswald Gruebel and I are aware that we are overseeing things for the time being, Villiger was quoted as saying. Our terms our limited, but they won't be two years, if we do our jobs well. But the question who will take over from Villiger or Gruebel hasn't yet been answered..

In November, Gruebel set a three- to five-year target of $15 billion annual pretax profit and said it would take about two years to reverse client withdrawals, starting from the first quarter of 2008.

UBS will publish its fourth-quarter results on February 9, and analysts say the bank may post its first quarter profit in more than a year.


Addressing the concern about banks being too big to fail, Villiger said the Swiss had adopted stricter regulations than other countries and that the problem was not size but linkage.

We ask ourselves, if we are really too big for Switzerland, Villiger said. UBS today is much smaller than it was before the crisis, and we believe that due to all these measures similar developments won't happen again in coming years.

He said cases like that of Britain's Northern Rock proved that collapses of small banks could be hard on the financial system.

We should never forget that in some cases large banks in Switzerland were stabilizing factors. Mortgage crises would have been worse if the there hadn't been big banks with their wide international risk management, he said.

U.S. tax authorities have said they have a deal with the Swiss government to produce information on U.S. accountholders at UBS. [ID:nLDE60P26N]

Villiger said that many people had already stepped forward voluntarily to U.S. authorities, and that there would be further negotiations between U.S. authorities and UBS, if the goals laid out in the existing agreement were not met.

That also involves the principle of proportionality, and the well-being of UBS must be taken into account, he said. The situation is unfortunate for UBS, because there's still some risk, which can affect the market.

(Reporting by Catherine Bosley)