A BP executive has been heckled at an oil conference in London while standing in for embattled chief executive Tony Hayward.

BP chief of staff Steve Westwell was interrupted twice during his address on Tuesday by protesters shouting "we need to end the oil age!" The hecklers were escorted out of the central London hotel by security.

Westwell says Hayward is "genuinely sorry" not to be at the conference, where he had been due to give a keynote address on about the global responsibilities of international oil companies.

Hayward pulled out of the conference Monday after stinging criticism for spending Saturday at England's Isle of Wight to see his yacht compete in a famous race. The outing drew an acerbic response from the White House.