Derek Wanless, group CEO of National Westminster Bank, left the bank yesterday following a Wednesday board meeting where his departure was "mutually agreed upon, according to bank spokesman Steve Colton. Bank Chairman David Rowland will take on the role of chief executive "for an indefinite period, said Mr. Colton. In addition, the bank hired former Lloyds of London Chief Executive Ron Sandler as director and group COO. Mr. Wanless resignation comes at a difficult time for NatWest as it tries to fight off a £21 billion ($35 billion) hostile bid by Bank of Scotland and following the collapse this week of its recent attempt to merge with Legal & General. Mr. Wanless will "stay on in a consultancy capacity to see off the ill-thought-out bid by Bank of Scotland, said Mr. Rowland in a press statement.