Iran's oil minister called for cooperation between crude producers inside and outside Opec, saying it was necessary in view of the global economic downturn, the official Irna news agency reported.

Oil Minister Gholamhossein Nozari, speaking a week before Opec ministers are due to meet in Vienna, also said on Sunday the producers group's members were almost completely complying with commitments to curb output, Irna said.

Nozari said the Organization of the Petroleum Exporting Countries would make a decision 'in regard to oil output' at its March 15 meeting after examining the crude market and the global economy, giving no detail on what that decision might be.

Opec member Venezuela has said it would propose another output cut if needed, echoing comment from other members.

Earlier this month, Nozari said he did not expect a further reduction decision in Vienna after Iran had previously suggested Opec could impose more curbs. He did, however, call for a mechanism to underpin prices.

'Under the current global economic conditions the cooperation of non-Opec oil producers (with Opec members) is absolutely necessary,' Irna quoted him as saying on Sunday.

He did not elaborate nor mention any countries by name. Russia is the largest oil producer outside Opec.

Crude prices have plunged more than $100 a barrel since a July peak of $147 as a weakening world economy hit fuel demand.