FILE PHOTO: A flag with the Organization of the Petroleum Exporting Countries (OPEC) logo is seen before a news conference at OPEC's headquarters in Vienna, Austria December 10, 2016. REUTERS/Heinz-Peter Bader/File Photo

LONDON (Reuters) - OPEC plans to meet with non-OPEC oil producers on the same day as its scheduled May 25 conference, sources familiar with the arrangements said, as they decide whether to extend supply cuts into the second half of the year.

Ministers from the Organization of the Petroleum Exporting Countries will convene at their Vienna headquarters. Joint talks with non-OPEC oil ministers will also take place that day, two sources said.

A number of key OPEC members including top exporter Saudi Arabia support extending their supply cut into the second half of 2017 if all participating producers, including Russia and other non-OPEC countries, agree, OPEC sources have told Reuters.

“It all depends on Russia’s position,” an OPEC delegate said on Wednesday.

Moscow has not stated whether it supports prolonging the curbs, although Energy Minister Alexander Novak said this month that Russia would soon start consultations with its own oil producers about the possibility of doing so.

The plan for same-day meetings suggests the issue will be settled more quickly than last year, when the deal was agreed. OPEC met on Nov. 30 to decide its own output cuts, and a gathering with non-OPEC took place more than a week later.

The schedule for May 25 is not final and could be changed nearer the time, the sources said.

Under the deal, OPEC is curbing its output by about 1.2 million barrels per day from Jan. 1 for six months in an attempt to eradicate a supply glut. Russia and 10 other non-OPEC producers agreed to cut half as much.

The accord has lifted oil prices, which are near $55 a barrel. However, still-large inventories and higher output from some producers such as the United States - which is not participating in the supply accord - have limited the rally.