OPEC heavyweight Saudi Arabia has made a sharp cut in oil output that had held at record rates around 10 million barrels a day for three months running to help offset a plunge in output from fellow OPEC member Libya.

The world's top oil exporter turned down the taps to 9.75 million barrels per day in October, versus 10.1 million the previous month, an industry source familiar with the matter told Reuters.

The kingdom lifted output to 10.05 million in August, the highest since records began in 1980, according to figures form the U.S. Energy Information Administration.

The industry source did not give a reason for the drop, only adding that supply to the market in October was 9.7 million.

The Organization of Petroleum Exporting Countries meets on Dec. 4 to chart production policy for 2014.