Crude oil prices were slightly down at the start of trading on Tuesday, despite reports that Saudi Arabia cut its crude exports to help boost prices.
International benchmark Brent oil traded at $57.28 per barrel at 0620 GMT for a daily loss of 0.5 percent, after ending Monday at $57.56 a barrel.
American benchmark West Texas Intermediate was at $48.55 a barrel at the same time and saw a 0.4 percent loss having closed Monday at $48.76 per barrel.
Saudi Arabia is planning to lower its crude oil exports to around 7.1 million barrels per day (mbpd) by the end of January to help boost oil prices above $80 a barrel, The Wall Street Journal reported OPEC officials as saying on Monday.
The world's largest crude oil seller exported around 7.3 mbpd of crude in December and 7.9 mbpd in November, according to the report.
Saudi-led OPEC and Russia agreed on Dec. 7 to curb their total crude oil production by 1.2 mbpd beginning on Jan. 1 for six months, but the plan so far has had little impact on crude prices.
On the demand side, weaker economic growth prospects worldwide for 2019 casts a shadow for overall global oil demand.
China and the U.S., the world's two biggest economies, restarted negotiations on Monday in Beijing to resolve their trade disputes.
U.S. Commerce Secretary Wilbur Ross said Monday that China and the U.S. could get "a reasonable settlement" that both countries "can live with," according to international media.
A trade agreement could mitigate the global economic slowdown and keep global oil demand high; however, failure to reach a deal would worsen economic growth prospects and keep a downward pressure on oil demand and prices, according to experts.
By Ovunc Kutlu