Reuters sources cited
OPEC experts are making "some progress" in a technical meeting in Vienna and the talks are continuing, according to an unnamed source cited by Reuters.
Oil is up nearly 4% on speculation that OPEC will deliver some kind of agreement.
Meetings began at 0930 GMT and Reuters reports:
"More than seven hours later, the first day's talks had yet to conclude but delegates said they were making headway and the meeting was scheduled to resume on Tuesday at 0900 GMT.
"Some progress," one of the delegates said. A second delegate said he was optimistic that the 14-country OPEC would reach a final agreement when its oil ministers meet in Vienna on Nov. 30.
Another source said there were "some concerns" from Iran, but discussions were ongoing and was confident there would be a deal on Nov. 30."
A key issue is the level at which Iran is expected to freeze its output but the report says most members are prepared to offer Iran flexibility on its targets.
The main meeting takes place Nov 30.