If patience and discretion are the hallmarks of a good central banker, then Jean-Claude Trichet, governor of the Bank of France, has shown he possesses these qualities in abundance.

For almost two years the anointed successor to Wim Duisenberg has born the strain of a judicial enquiry into his role in the bank collapse of Credit Lyonnais without knowing whether it will prejudice his chances of becoming the next governor of the European Central Bank.

In this time he has said nothing in public: even in private he brushes aside any questions to ensure he remains above the fray.

Mr Trichet is one of four senior civil servants being investigated for the decisions taken during 1992 and early 1993 to deal with the fast moving crisis at Credit Lyonnais. At the time Mr Trichet was director of the treasury and the allegations concern the "publication of false information to the markets and presentation of inaccurate accounts" for the year 1992 and the first half of 1993.

In 1994 a parliamentary enquiry examined the role of senior civil servants in handling the bank and in Mr Trichet's case exonerated him.

The judges have however placed all this under the microscope again: in so doing they have raised big issues about the responsibility of senior civil servants when carrying out the orders of their governments or acting in the state's best interests.

Their investigation was wound up at the end of last September and a decision on whether to institute proceedings was expected early in the New Year. But this is now unlikely before March. If dropped Mr Trichet would then be free to move on to the ECB.

But if there is a case to answer then this would not begin before late 2002, early 2003. So long as these uncertainties persist, the French government cannot be seen to search for alternative candidates for the ECB since this could compromise Mr Trichet's presumed innocence.

Wim Duisenberg's announcement yesterday that he would stay to June 2003 at the ECB helm offers breathing space. But it does not resolve the issue should Mr Trichet have to fight to clear his name in the courts, no matter how flimsy the charge.

It is this possibility that has led to other names appearing in the frame - although all are considered distant outsiders to Mr Trichet's favoured candidacy.

Among them is Philippe Maystadt, European Investment Bank president, and one of the architects of Emu and its fiscal stability pact. Yesterday at the EIB's annual meeting Mr Maystadt reiterated his commitment to his current job. "It even surprised me as to how much I would enjoy it. I am passionate about it," he said.

Others mentioned as possible successors are Jean-Claude Juncker, the prime minster of Luxembourg - who said only a few months ago that he had been secretly approached to gauge his interest, or Guy Quaden, Belgian National Bank chief.

Poll shows British support for euro membership is weakening

By Brian Groom, Political Editor Wim Duisenberg's departure will come too late to have a big impact on Britain's debate on joining the euro, which showed signs yesterday of swinging against Britain's entry.

An ICM poll for No, the anti-euro campaign, showed the majority against British membership had risen to 60-27, compared with 56-31 a month ago. The No campaign said the poll took opinion back to September levels, suggesting the softening of the public mood in the run-up to the introduction of euro notes and coins had faded, as happened after the currency's launch in 1999.

In theory, Mr Duisenberg's decision to cut short his tenure as European Central Bank president ought to help supporters of UK entry. He has been pilloried in the eurosceptic media for what were received as gaffes, earning him the tabloid sobriquet of "Dim Wim".

Pro-euro campaigners believe that if a successor were chosen who was enthusiastic about Gordon Brown's case for reforming the ECB's monetary policy framework, it would help overcome the chancellor's reservations about joining.

But Mr Duisenberg is not due to stand down until July 2003, by which time the UK debate may have been settled until after the next general election. The government has promised an economic assessment by June 2003: a referendum will be called only if it produces a "clear and unambiguous" case in favour.

Britain is likely be happy if Jean-Claude Trichet, Bank of France governor, is the successor.

The Treasury was pleased last month when two senior French politicians backed ECB reform to introduce UK-style monetary policy arrangements, including changes to the inflation target, publication of minutes and even a European version of the UK's monetary policy committee. But Britain, as a non-member of the eurozone, does not have a vote on Mr Duisenberg's successor and is unlikely to back a candidate.