LONDON (Dow Jones)--BP PLC (BP) will change the way it operates and sell up to $30 billion of assets to fund its massive liabilities from the Gulf of Mexico oil spill, but the company will not be fundamentally changed and will continue to explore for oil in frontiers like deep water, senior company executives said Tuesday. BP's Chairman Carl-Henric Svanberg said he believes its actions before the explosion aboard the Deepwater Horizon drilling rig that triggered the worst oil spill in U.S. history weren't grossly negligent. However, Chief Executive Tony Hayward said he had become a "lightning rod" for public anger over the spill and the only way for BP to move forward in the U.S. was for him to step down. Hayward defended BP's response to the oil spill, describing it as the largest operation of its kind in history that few other companies would have been able to mount. -By James Herron, Dow Jones Newswires; +44 (0)20 7842 9317; james.herron@dowjones.com (END) Dow Jones Newswires July 27, 2010 03:00 ET (07:00 GMT)