Dominique Strauss-Kahn’s days as head of the International Monetary Fund look numbered. Following his arrest in New York on sex charges, there are growing calls for him to step down immediately to avoid damaging the institution.

Natural justice demands that Mr Strauss-Kahn should not be pushed until he has had a chance to present his side of the story. Only when the case proceeds to trial does the argument for his departure become unanswerable.

The IMF need not panic if this comes to pass as it has a competent deputy in place in the shape of John Lipsky. It is to be hoped that he can if necessary be persuaded to stay on beyond August, when he had planned to step down. But while the search for a replacement should not be rushed, it cannot be long delayed. With the IMF at a critical juncture, a leadership vacuum must be avoided.