Oil futures rallied on Tuesday, with the U.S. benchmark scoring its largest one-day gain in three weeks as tensions between Turkey and Russia raised concerns over the possibility of disruptions to energy output in the region.

Turkey shot down a fighter jet claimed by Russia after it apparently crossed into Turkish airspace. “The Mideast is slowly or quickly grinding towards an event which hits the energy system over there,” said Richard Hastings, macro strategist at Seaport Global Securities.

Obama urges Turkey and Russia to talk, not escalate

“That would occur because oil is still the dominant economic engine for so many participants,” he said. “It’s strategically the first and biggest risk factor.”

On the New York Mercantile Exchange, January West Texas Intermediate crude CLF26, climbed by $1.12, or 2.7%, to settle at $42.87 a barrel. The increase was the largest single session percentage and dollar gain since Nov. 3. The settlement, meanwhile, was the highest since Nov. 11.

Brent crude UK:LCOF6 rose $1.29, or 2.9%, to $46.12 a barrel on London’s ICE Futures exchange.

Comments Monday by Saudi Arabia that it is ready to cooperate with other producers to support the market added to the bullish sentiment.

But “this could be just empty promises,” said Daniel Ang, energy analyst at Phillip Futures. “At the end of the day, as long as nothing concrete is said, we would hold our horses on a bullish run for prices.”

OPEC and other major producers like Russia are still pumping crude at near record levels and expectations of a stronger U.S. currency are also bearish for oil prices with the market expecting the U.S. Federal Reserve to raise interest rates at its meeting in December.

“Irrespective of [Saudi Arabia’s] statements we still think that the oil price has a challenging time ahead as we move into the first half of 2016 with rising stocks…and a likely stronger [U.S. dollar],” said Bjarne Schieldrop, commodities analyst at SEB Markets.

The American Petroleum Institute will release its weekly data on petroleum supplies late Tuesday. The U.S. Energy Information Administration’s report will be published on Wednesday.

Analysts polled by Platts expect to see a fall of 200,000 barrels in crude inventories, along with a drop of 1.1 million barrels in distillate stockpiles and a fall of 400,000 barrels for gasoline supplies.

With product inventories expected to decline, December gasoline US:RBZ5 jumped 7.7 cents, or 5.9%, to $1.39 a gallon on Nymex. December heating oil US:HOZ5 tacked on 2.5 cents, or 1.9%, to $1.40 a gallon.

December natural gas US:NGZ15 ended at $2.20 per million British thermal units, down a penny, or 0.5%, after Monday’s 3% climb.