Oil prices decline on glut concerns

Oil prices tumbled Friday on renewed concerns that increasing U.S. production and inventory will offset leading Gulf crude producers' production cut efforts.

U.S. oil production is still rising as rigs classified as drilling for oil are up 5 to 688 this week, according to data released by oilfield service company Baker Hughes on Friday. This marks the 14th consecutive week of U.S. rig count increase.

Earlier this week, the U.S. Energy Information Administration forecast that crude output at major U.S. shale plays will increase to 5.2 million barrels a day in May.

Overseas, Organization of the Petroleum Exporting Countries (OPEC) members Saudi Arabia and Kuwait signaled that the Organization of the Petroleum Exporting Countries and other producers, including Russia, would likely extend their oil output cut beyond June, according to media reports.

The West Texas Intermediate for June delivery decreased dollars to settle at 49.62 dollars a barrel on the New York Mercantile Exchange, while Brent crude for June delivery erased 1.03 dollars to close at 51.96 dollars a barrel on the London ICE Futures Exchange. Endit