The Organization of Petroleum Exporting Countries (OPEC) has agreed to cut production by 750,000 barrels a day.
The surprise news triggered an immediate spike of more than 5 percent in crude prices, as markets had expected the Algiers meeting to end without agreement.
In London benchmark Brent North Sea crude for November delivery rose $2.72 to $48.69, while in New York a barrel of West Texas Intermediate (WTI) was up $2.38 to $47.05.
OPEC members, whose countries produce 40 percent of the world’s crude oil, agreed to cut their output to 32.5 million barrels per day.
An informal OPEC meeting opened in Algiers earlier Wednesday to discuss a possible freeze in output by the cartel, with the aim of raising prices which have fallen by more than half since mid-2014.