LONDON (Dow Jones)--The chief executive of BP (BP.LN), Tony Hayward, has been negotiating terms for stepping down from the role and a formal announcement is likely within 24 hours, the BBC reported on its website Sunday, without citing sources. Hayward has come under fire following the Gulf of Mexico oil spill and his handling of what has become one of the worst environmental disasters in the U.S. -By London news desk, Dow Jones Newswires; [email protected] (END) Dow Jones Newswires July 25, 2010 09:32 ET (13:32 GMT)