Opec and the oil cartel's allies discuss an agreement to reduce oil production by at least 1.3 million barrels a day. It states four sources for Reuters.
According to the data, however, Russia's opposition to a significant reduction in production at the moment is the main obstacle to such an agreement.
The oil ticket will meet during Thursday in Vienna, then hold talks with Russia and other partners the following day.
Opec's largest producer and informal leader, Saudi Arabia, has flagged a need to lower production but has met resistance from US President Donald Trump who wants to see lower oil prices.
At the same time, the sources also indicate that Russia's position is a key factor in the negotiations. According to previous data, the country is ready to reduce its production by 140,000 barrels a day, while Opec wants to see a cut by about twice.