Crude oil prices remained up on Sunday (April 9) compared to the previous day.
The price of Brent oil was at $55.23, up from $54.89, while U.S. WTI crude was at $52.31 from $51.70.
OPEC and non-OPEC producers on December 10 reached their first deal since 2001 to jointly curtail oil output and ease a global glut after more than two years of low prices that overstretched many budgets and spurred unrest in some countries.
With the deal finally signed after almost a year of arguing within the OPEC and mistrust in the willingness of non-OPEC Russia to play ball, the market's focus will now switch to compliance with the agreement.
Producers from outside the 13-country group agreed on December 10 to reduce output by 558,000 barrels per day, short of the initial target of 600,000 but still the largest contribution by non-OPEC ever.
Oil prices have more than halved in the past two years after Saudi Arabia raised output steeply in an attempt to drive higher-cost producers such as U.S. shale firms out of the market.
The plunge in oil to below $50 per barrel - and sometimes even below $30 - from as high as $115 in mid-2014 has helped reduce growth in U.S. shale output.