Benchmark Brent crude was at $65.31 per barrel at 0650 GMT, down 23 cents after hitting a session high of $65.75. Oil prices already tumbled 3 percent on Thursday as a resurgent dollar erased gains from the past two sessions, and after some U.S. producers said they would ramp up drilling after months of falling activity if prices continued to rise. “U.S. producers… indicated they would ramp up drilling activity if prices continued to rise,” ANZ bank said in a note.