(Adds quote) LONDON (AFP)--Energy giant BP PLC (BP) must be given "certainty" about its liabilities from the Gulf of Mexico oil spill, British Prime Minister David Cameron said Wednesday. "While it is important that they pay reasonable claims--BP accept this themselves--they do need a level of certainty," he told BBC radio, hours ahead of a meeting between BP's chairman and U.S. President Barack Obama. (END) Dow Jones Newswires June 16, 2010 09:56 ET (13:56 GMT)