Oil prices slipped on Tuesday as crude output rose in virtually every major export region despite plans by OPEC and Russia to cut production, triggering fears that a fuel glut that has dogged markets for more than two years might last well into 2017.
International Brent crude oil futures fell $1.03, or 1.9 percent, to $53.91 per barrel by 2:36 p.m. ET (1936 GMT). U.S. West Texas Intermediate (WTI) crude settled down 86 cents, or 1.7 percent, at $50.93 a barrel, for the first down day in five sessions.
Brent rose more than 15 percent over the four sessions since the Nov. 30 OPEC meeting. The Brent front-month has outperformed the U.S. contract since the OPEC meeting, with its premium over WTI reaching $2.29 a barrel earlier on Tuesday, its highest since August.
Analysts said the boon from last week's Organization of the Petroleum Exporting Countries decision has faded as they now look to factors that may undermine the cartel's promise such as record production, Russia's plans and the reaction of U.S. shale producers.
"Adherence to assigned OPEC quotas is apt to be limited and enforcement of such nearly impossible," Jim Ritterbusch, president of Chicago-based energy advisory firm Ritterbusch & Associates, said in a note.