Ron Sandler has quit his non-executive chairmanship at Computacenter with immediate effect following his decision to run Northern Rock while it is under public ownership.

Sandler has been named chairman of the newly nationalised bank. He had previously been overseeing government efforts to find a white knight bidder after it was floored by the credit crunch last year.

IT reseller and service group Computacenter said in a statement today that Sandler's "well-publicised commitment" to help the government try and steady the ship at Northern Rock meant it was necessary for him to step down from his role at Computacenter.

It added that the search was already on to replace South Africa-born Sandler, who has been a member of the board in a non-executive role for several years.

Chancellor Alistair Darling announced yesterday that Northern Rock would be nationalised in a last-gasp attempt to pull the ailing bank out of trouble.

In September last year, the Newcastle-based mortgage lender was forced to ask the Bank of England to bail it out with an emergency £25bn loan, which prompted the first emergency cash run on a UK bank for more than 140 years.

According to the Financial Times, Sandler, who has previously overseen turnaround efforts at the Lloyds insurance market and NatWest, will be paid £90,000 a month in his new job. ®