Opec yesterday was split over plans to suspend output limits should the US launch war on Iraq, fuelling fears of a further spike in the price of oil.
Iran said it opposed a bid by Western-friendly Opec states for a policy that Tehran says implies support for a US attack, by controlling oil prices.
Gulf Opec powers Saudi Arabia and Kuwait are hoping to get backing at meeting of the Organisation of the Petroleum Exporting Countries being held today to set aside production quotas if war stops Iraqi exports.
Riyadh also is trying to convince importing nations there is no need for a release in the event of war from their emergency strategic stockpiles.
"Iran will not back politically motivated decisions," Iranian Oil Minister Bijan Zanganeh told the official IRNA news agency.
Opec should not adopt any policy that implies support for a "US military assault against one of Opec's member states," ZMr anganeh said.
High prices, acting as a brake on world economic growth, edged up two cents for US crude to $37.80 a barrel, approaching the record $41-a-barrel highs set in the 1990 Gulf crisis.
"The last thing we need now is to worry about oil supplies. People are not looking for a hardline Opec," said Peter Gignoux, head of the energy desk at Salomon Schroder Smith Barney in London.
"This is a perfect opportunity for OPEC to prove that it is a friend to the world community."
Delegates said Iran's position was likely to find support from Libya, at least. That means the group may simply leave current output limits in place and signal its intention to ensure stable supplies in the event of a disruption.
"We won't be able to make any explicit statements but we will have to reach an understanding that those countries capable may produce what they can, which effectively is a suspension of quotas," said a non-Arab delegate.
"The Iranians can comfortably take a rhetorical position and still benefit from the fact that there's pressure on Opec to pump as much as possible," commented Raad Alkadiri of Washington's Petroleum Finance Corp.
Behind the scenes Saudi has made clear that it is prepared to open the taps to the limit, with or without Opec backing.
The only Opec producer with any significant spare capacity, Riyadh has lifted output sharply in recent weeks and is now pumping more than nine million barrels daily of its 10.5 million bpd capacity.
Saudi Oil Minister Ali al-Naimi will press his case for Opec to be allowed to go it alone without a release of consumer reserves at a meeting in Vienna today with US Energy Secretary Spencer Abraham.
Saudi will be stretched to fill a war shortage. Iraq's 1.7 million barrels daily is almost certain to shut and Kuwait says it could close up to 700,000 bpd near its northern border with Iraq from where US troops are poised to invade.
Riyadh's ally, the United Arab Emirates, said that Opec might not have enough spare capacity to cover war-related outages.