Oil surged to the highest levels in more than three years as tensions simmered in the Middle East, signaling optimism that a glut that has crippled the market for years is ending.

U.S. crude futures jumped $1.31, or 2%, to $66.82 a barrel Wednesday on the New York Mercantile Exchange. Brent, the global benchmark, rose $1.02, or 1.4%, to $72.06 a barrel on ICE Futures Europe. Both benchmarks are at their highest levels since December 2014.

More than a year’s worth of production cuts by the Organization of the Petroleum Exporting Countries has helped set the stage for this rally, gradually whittling away at a glut that kept prices low for more than three years. Venezuela’s oil output is also in freefall as the country’s economic turmoil deepens. With the prospect of renewed sanctions against Iran, some analysts and investors say prices are poised to climb even higher.

Gary Ross, global head of oil analytics and chief energy economist at S&P Global Platts, has been predicting that Brent prices would rise to $75 to $80. He said Wednesday that a “perfect storm” of falling supplies and geopolitical saber rattling could push prices even higher.

“What’s unfolding is an extraordinarily vulnerable situation for the market—you’re at great risk of a price spike if something unexpected happens,” he said. “We have no cushion.”