Saudi Arabia's Energy Minister Khalid al-Falih said on Monday that OPEC should not cut oil supply too steeply
OPEC's second biggest producer Iraq said over the weekend that it wants to raise output further in 2017
Brent futures were down 20 cents, or 0.39 per cent, at $51.66 per barrel
There were also risks of forced supply disruptions, especially in North Africa, Nigeria, and Venezuela
International Brent crude futures were down 24 cents at $51.62 per barrel
Benchmark Brent crude was trading at $51.38 per barrel, up 51 cents, or 1.0 per cent
In international oil markets, benchmark Brent crude futures were trading at $51.29 per barrel, up 42 cents, or 0.8 per cent
In international oil markets, benchmark Brent crude futures were trading at $51.29 per barrel, up 42 cents, or 0.8 per cent
International Brent crude oil futures were trading at $50.79 per barrel
International benchmark Brent crude futures were trading at $50.25 per barrel
Also, doubts are that OPEC's first planned output cut in eight years would make a substantial dent in the global crude glut
OPEC agreed on Wednesday to cut output to 32.5-33.0 million bpd from around 33.5 million bpd
Oil prices extended gains after rising nearly 6% on Wednesday after OPEC struck a deal to limit crude output
Brent crude rose 12 cents to $46.09 a barrel
US WTI crude had climbed 27 cents to $44.94 a barrel and Brent crude rose 32 cents to $46.29 a barrel
Major oil producers are gathering in Algeria for a three-day meeting that could see moves to cut or freeze oil output
US West Texas Intermediate crude fell 6 cents to $45.87 a barrel, after rising $1.45
Brent crude futures slipped 43 cents to $46.91 a barrel after closing up $1.46, or 3.2%
Concern about global oversupply has depressed oil prices since mid-2014
US EIA on Wednesday reported a 6.2 million-barrel drop in crude oil inventories last week to 504.6 million barrels