LONDON- OPEC and other oil producers will debate on Thursday oil cuts as big as 20 million barrels per day, equivalent to about 20% of global supplies, one OPEC source and a Russian source told Reuters.

"That is a global deal," the OPEC source said.

He did not specify if the United States would be involved - something Russia and OPEC producers have insisted on.

Another OPEC source and a separate Russian source told Reuters that Russia and Saudi Arabia had managed to remove their main obstacles to agreeing a new deal on oil cuts.

(Reporting by OPEC team; Writing by Dmitry Zhdannikov; Editing by Edmund Blair) ((Dmitri.Zhdannikov@thomsonreuters.com;))