Oil rose on Tuesday above $75 a barrel to its highest since November 2014, supported by OPEC-led production cuts, strong demand and the prospect of renewed U.S. sanctions on Iran. Brent crude, the global benchmark, hit its highest since OPEC on Nov. 27, 2014 turned its back on curbing output to support prices, a move that triggered a battle for market share and helped deepen a collapse to $27 in early 2016. Oil prices began to recover in 2016 as the Organization of the Petroleum Exporting Countries discussed a return to market management with the help of Russia and other non-members. A supply-cutting deal took effect in January 2017. Brent traded as high as $75.27, gaining for a sixth day, and was up 37 cents at $75.08 by 0845 GMT. U.S. crude rose 51 cents to $69.15, having hit its highest since Nov. 28, 2014 on Thursday. The United States has until May 12 to decide whether to quit a nuclear deal with Iran and reimpose sanctions against OPEC's third-largest producer, tightening global supplies. "Currently, all bets are off on the U.S. staying in the nuclear agreement," said Tamas Varga of oil broker PVM, who added this concern was the most significant element of Brent's recent rally. Stephen Innes, head of trading for Asia-Pacific at futures brokerage OANDA, said new sanctions against Tehran "could push oil prices up as much as $5 per barrel". OPEC's supply curtailments and the threat of new sanctions are occurring just as demand in Asia, the biggest oil-consuming region, has risen to a record as new and expanded refineries startup from China to Vietnam.