Former Royal Bank of Scotland chairman Sir Tom McKillop resigned yesterday – from the board of oil giant BP.

Sir Tom – caught up in the row over former RBS chief executive Sir Fred Goodwin’s £703,000 pension – will step down at BP’s annual meeting on April 16.

He joined the BP board as a non-executive director in 2004 and served on its remuneration committee, earning £95,000 in 2008.

Sir Tom said he felt “this is an appropriate step for me to take at this time”.

BP chief executive Tony Hayward said: “Tom has provided wise counsel to me, my executive colleagues and, indeed, the entire board.

“I am sorry he did not feel he could continue to serve with us.”

BP chairman Peter Sutherland added: “It is a matter of great regret that Sir Tom has chosen to retire. He is a colleague of the highest integrity.”

Sir Tom, who served as chief executive of pharmaceuticals giant AstraZeneca until December 2005, was also a non-executive director of Lloyds TSB – now Lloyds Banking Group – until 2004.

He resigned as RBS chairman in February in a boardroom shake-up as a new management team attempts to salvage the ailing bank.

Sir Tom will go down in history as the man at the helm as RBS recorded the biggest loss in UK corporate history - and was forced into the arms of the taxpayer to survive.

His decision to step down from BP could also signal an unwillingness to damage the oil major by association due to the current furore over Sir Fred’s pension.