Vienna - The price of crude oil produced by the Organization of the Petroleum Exporting Countries (OPEC) dropped below the 90- dollar mark on Tuesday, OPEC said on Wednesday.

One barrel (159 litres) of OPEC crude stood at 86.69 dollars Tuesday, down 4.57 dollars from 91.26 dollars on the previous day.

In its latest Monthly Oil Market Report, OPEC lowered its forecasts for global oil demand growth.

The cartel expects consumption growth to reach 880,000 barrels per day this year, 120,000 barrels per day less than previously forecast. The estimate for 2009 was lowered by 20,000 barrels per day, to 870,000 barrels per day.

Supply forecasts by non-OPEC producers were also lowered, by 70,000 barrels per day each for this and for the next year.

OPEC calculates an average basket price based on 13 important brands produced by its members. (dpa)