VIENNA -- The Organization of Petroleum Exporting Countries ended a two-day general meeting Saturday in Vienna by formalizing a plan to reduce oil output by about one million barrels per day from April 1.

OPEC hopes the step will prevent oil prices from declining, as global oil demand is expected to decrease with the slowdown in the U.S. and Japanese economies.

The cut will shave limits for 10 OPEC members, excluding sanctions-bound Iraq, by 4 percent to 24.2 million barrels per day.

The step is OPEC's second reduction this year. In January, the cartel cut output by 1.5 million barrels per day after having maintained a steady level of production since April 1999.

OPEC ministers reached a basic accord on the reduction plan on Friday in time for a formal announcement Saturday.

OPEC is also scheduled to hold an extraordinary general meeting in June in Vienna to assess the effects of the latest cut and set new production quotas.