Oil prices rose sharply on Monday, lifted by a plunge in the dollar that could spur demand.
This follows the release of the weak U.S. jobs data on Friday, which offset losses for financial stocks and some energy companies.
Brent crude futures rose as high as $50.10 but retreated to be up 38 cents at 50 dollars and 2 cents a barrel earlier on Monday.
U.S. crude futures were also up 41 cents at 49.03 dollars a barrel.
A weaker dollar supports fuel demand in the rest of the world as it makes dollar-traded oil imports cheaper and this is good news for African producers who are facing a sluggish economy.
The developments happened as members of the Organization of the Petroleum Exporting Countries closed their summit with no agreement on a production cap at the 169th Opec summit in Vienna.