Barclays boss John Varley is to step down three months earlier than planned, paving the way for Bob Diamond to take control next month.
The bank said in September that Mr Varley would step down next March. It has since brought forward its succession plans, after successfully completing the handover to Mr Diamond, who will take full control on January 1.
Marcus Agius, Barclays' chairman, said Mr Varley felt the time was right to step back as chief executive: "Over the last three months, John and Bob have made good progress in completing the transition."
He added: "The speed with which the transition has been completed reflects the continuity in management and strategy that the succession provides."
Following his departure from the board, Mr Varley will remain a senior advisor on regulatory issues to Mr Diamond and the board until the end of September. He is expected to keep his full salary for the full financial year. Last year he picked up £1.1m, though he did not receive a bonus.
Mr Diamond headed up Barclays' investment banking business, so his appointment sparked fury. The Liberal Democrat Treasury affairs spokesman said it "put two fingers up to the Government". Many were averse to an executive from so-called "casino" banking taking the reins at a group that also offers retail banking. Mr Diamond is set to earn £1.3m in basic pay, with a bonus package that could soar as high as £11.5m next year.Reuse content