Oil held Tuesday’s gain to trade near a four-month high after Russia reaffirmed its commitment to the OPEC+ production cuts and disruptions in Venezuela added to supply concerns.

Futures in New York were steady after rising 1.9 percent in the previous session. Russia, the world’s second-biggest crude producer, is on track to reach its pledged output cut of 228,000 barrels a day by the end of March, Energy Minister Alexander Novak said. Venezuela’s main oil ports were said to remain shut on Tuesday after a power outage halted exports a day earlier.

Oil is poised for the best quarterly gain since 2009 as the Organization of the Petroleum Exporting Countries and its allies curbed production to clear excess inventories. Signs the U.S. shale boom is running out of steam, power outages in Venezuela and U.S. sanctions on Iran are also supporting prices, while the demand side is still uncertain as investors wait to see if the U.S. and China can resolve their trade war.

“Russia is making good on its promise,” said Takayuki Nogami, chief economist at Japan Oil, Gas and Metals National Corp. in Tokyo. “Investors are becoming more confident they can trust Russia’s relationship with Saudi Arabia, and supply disruptions in Venezuela are raising concerns the market will tighten further.”

West Texas Intermediate gained 4 cents to $59.98 a barrel on the New York Mercantile Exchange as of 9:42 a.m. in Singapore. The contract climbed $1.12 to $59.94 on Tuesday. It has risen 32 percent so far this quarter.

Brent for May settlement rose 10 cents to $68.07 on the London-based ICE Futures Europe exchange. The contract advanced 76 cents, or 1.1 percent, on Tuesday. The global benchmark crude was at a premium of $8.07 to WTI.