Oil prices settled at a more than one-month high on Thursday as optimism over an OPEC plan to limit output was offset by questions over its ability to rebalance a heavily over-supplied market.
The Organization of the Petroleum Exporting Countries agreed on Wednesday to cut output to 32.5 to 33 million barrels per day (bpd) from around 33.5 million bpd, estimated by Reuters to be the output level in August.
OPEC said other details of the plan will be known at its policy meeting in November, leaving unanswered when the agreement will come into effect, what new quotas for member countries will be and for what periods, and how compliance will be verified.
Earlier in the day, oil was down, with crude futures retreating from their 6-percent gain on Wednesday, the biggest in a day since April. A steady dollar and weak U.S. stock market also limited some of the upside in oil in early trading.