U.S. West Texas Intermediate (WTI) was up 33 cents or 0.7 percent to $48.40 a barrel.
The cartel's production dropped by 79,100 barrels per day (bpd) to 32.76m bpd last month, according to secondary sources that measure Opec output. Analysts forecast that crude inventories last week rose while products drew down, ahead of The American Petroleum Institute (API) data on Tuesday and the U.S. Department of Energy's Energy Information Administration (EIA) reporton Wednesday.
Saudi Arabian Energy Minister Khalid Al Falih discussed with his Venezuelan and Kazakh counterparts the possible extension of the global oil supply cut pact beyond March 2018, the Saudi energy ministry said late on Sunday.
The latest inventories data will come back into focus with the API data due for release after Tuesday's NY close with the latest EIA data on Wednesday.More news: Pelosi declines to endorse Sen. Bernie Sanders' single-payer healthcare bill
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Crude oil prices were mixed in Asia on Monday as investors focused on prospects of another extension for an OPEC-led oil cut into the middle of next year and as Hurricane Irma struck Florida with less force than feared. That is "because Texas has twice the oil consumption per capita of Florida given the significant concentration of refining and petrochemical capacity on the U.S. Gulf Coast", they said.
The firm said "given the only modest impact Harvey had on oil production, the combined demand loss generated by these two hurricanes will be a bearish shock for global oil balances in September".
"It is clear that the rebalancing process is underway, supported by the high conformity levels of OPEC member countries and participating non-OPEC countries to the production adjustments" in the cooperation agreement, OPEC secretary general Sanusi Barkindo said in a speech in Oxford on Monday.
The deal to curb output propelled crude prices above $58 a barrel in January but they have since slipped back to a $50 to $54 range as the effort to drain global inventories has taken longer than expected.
Stretching the duration of OPEC production limits by three months or more would fall under a worst-case scenario that ministers are now contemplating, the people said, asking not to be named because the talks were private.