Oil rose on Wednesday, with Brent crude perched above $40 a barrel as hopes for a meeting of top producers that could cap output upstaged forecasts that U.S. data due later in the day would show record high inventories for the fourth straight week.

Producers in and outside the Organization of the Petroleum Exporting Countries plan to meet in Moscow on March 20 to discuss an output freeze, an Iraqi oil official told state newspaper Al-Sabah. Russia's energy ministry said no date or place had been set for the meeting.

In the United States, the government-run Energy Information Administration was scheduled to issue at 10:30 a.m. EST a report that analysts polled by Reuters think will cite a 3.9 million barrels build in crude inventories last week.

Worries about too much oil supply caused global benchmark Brent to fall 3 percent on Tuesday, snapping a six-day rally after hitting 2016 highs above $40. But buying in crude returned on Wednesday as talk of OPEC action gathered momentum, while U.S. gasoline also rallied on expectations of an early rally to the peak summer driving season.

"It's going to be volatile for sure," Scott Shelton, energy broker at ICAP in Durham, North Carolina, describing potential market action for the day.

Brent LCOc1 was up 58 cents, or 1.5 percent, at $40.23 a barrel by 9:51 a.m. EST.

U.S. crude CLc1 rose 62 cents to $37.12.

Oil prices have risen by around 25 percent since Saudi Arabia, Qatar, Venezuela and non-OPEC exporter Russia said in mid-February they would leave supply at January's levels if there was enough support from other producers.

Energy consultancy Wood Mackenzie said it expected "the annual average price for 2016 to be lower than 2015 and then recover in 2017, reflecting large oversupply and high stock levels during the first half of 2016."

"Add all this momentum for actually increased talks between OPEC and non-OPEC - if there is a freeze agreement of some sort, then it could (form) the bridge to the tighter supply/demand balance in the second half," said Petromatrix crude oil strategist Olivier Jakob.

Credit ratings agency Moody's warned of the potential for more output declines and defaults in debt servicing by oil producing countries due to low oil prices.