Opec agrees to slash oil production

Opec oil ministers agreed today to cut crude oil output by one million barrels a day - 4% of their official target level.

The decision by all 11 members of the Organisation of Petroleum Exporting Countries is aimed at supporting crude prices at around 25 dollars a barrel in the face of eroding demand in the group’s key markets in the United States, Europe and Asia.

The cut is to take effect on September 1.

Energy analysts said the move would indeed shore up prices, but not to the point of causing serious pain for consumers in importing countries.

‘‘You will see a temporary rally,’’ said Edward Ennis of SG Securities in London. ‘‘It will not stop the decline in crude price.’’

Opec, which pumps about 40 percent of the world’s oil, has a current production target of 24.2 million barrels a day. It has already reduced its official production twice this year by a total of 2.5 million barrels a day.

Ministers announced their latest cut in output in a terse communique, after conferring privately by telephone.

The ministers are keeping an ‘‘open option to hold an extraordinary meeting soon if the market warrants it,’’ the communique said.

Opec is anxious to keep its benchmark crude price at no less than 25 dollars a barrel.

‘‘From what the balance of supply and demand looks like for the fall, they’ll achieve that,’’ said Jan Stuart, head of energy research in New York for the Dutch bank ABN AMRO.

At the very least, Stuart said, Opec will succeed in putting ‘‘a floor’’ under crude prices.

Crude prices have slid lower since the cartel’s ministers agreed to hold output steady at their last meeting on July 3.