BP safety committee chief to leave board Sir William Castell, the head of BP's safety committee, will retire from the board of the UK oil group this April, in the latest shake-up at the top of the company since the Gulf of Mexico disaster almost two years ago. News of the impending departure comes just days before BP unveils its results for the fourth quarter alongside a strategic update on Tuesday. Investors are hoping for a rise in the dividend that BP suspended at the height of the crisis, which followed the oil spill from the Macondo well in April 2010. Although the company reinstated its pay-out last February, it did so at a much lower level. But any decision on the dividend will need to be finely balanced. While the high oil price and the proceeds of a disposal programme have helped swell BP's coffers - the UK oil group is sitting on cash of about $20bn and signalled last year that it expects cash flow to increase by 50 per cent by 2014 - a higher pay-out is not a certainty. BP's board, led by Carl-Henric Svanberg, chairman, may need a substantial chunk of that cash to pay for an eventual settlement over liabilities for the Gulf of Mexico accident and spill. Bob Dudley, BP's chief executive, will also come under scrutiny on Tuesday and will need to demonstrate that the company is firmly back on a growth track after hailing a turnround last October. Sir William, who is also the senior independent director at BP, had decided not to stand for re-election at the annual meeting in April, BP said in a statement on Friday. Sir William has been on the board for nearly six years. His decision to leave comes after he suffered a big vote against his re-election at last year's annual meeting, with 43 per cent of shareholders unwilling to support him. Andrew Shilston, already a non-executive on the BP board and previously finance director of Rolls-Royce, will succeed Sir William as the senior independent director. BP also announced that Ann Dowling, head of the department of engineering at the University of Cambridge, will join the board as a non-executive.