OPEC will meet non-OPEC countries to finalize a global oil limiting pact on December 10 in Vienna, two sources told Reuters on Saturday.
Two OPEC sources earlier said the meeting was due to take place in the Russian capital Moscow, but later said that plan had changed.
OPEC agreed this week to reduce output by around 1.2 million barrels per day (bpd) beginning in January in a bid to reduce global oversupply and prop up prices.
It hopes non-OPEC countries will contribute another 600,000 bpd to the cut. Russia has said it will reduce output by around 300,000 bpd.