OPEC and non-OPEC oil producers look poised to agree at a meeting on Thursday to extend output cuts until the end of 2018, four OPEC sources said as the group seeks to clear a global glut of crude and avoid another price crash.
Some last-minute debate was still possible on the language of an expected statement, with non-OPEC Russia pushing for a clear message on how to exit the cuts so the market is prevented from overheating by flipping into a deficit too soon.
The producers' current deal, under which they are cutting supply by about 1.8 million barrels per day (bpd) in an effort to boost oil prices, expires in March.
"They will agree on the nine months," an OPEC delegate said, adding that a meeting of the Organization of the Petroleum Exporting Countries, due to start around 0900 GMT, was expected to be smooth.
A second source said: "No surprises ... all are for nine months."
Two other sources made similar remarks. The OPEC meeting will be followed by a gathering of OPEC and non-OPEC producers led by Russia at around 1400 GMT.
The 14-member OPEC and Russia have signalled that they may review any extension of the deal when they meet again in June if the market overheats.
With oil prices rising above $60 per barrel, Russia has expressed concerns that such an extension could prompt a spike in crude production in the United States, which is not participating in the deal.