After a decade of awesome profits and influence, OPEC's prolonged failure to agree on prices and quotas has seriously undercut its credibility. It may even break up the cartel altogether, since the disagreements which surfaced here will continue long after these meetings end.
This is the view of a number of oil analysts, commentators, and economists in London as OPEC struggled to agree on prices and production quotas in a period of slack world demand.
One possibility now is that the Gulf oil states led by Saudi Arabia might split off into a nucleus of their own, based on their existing grouping known as the Gulf Cooperation Council.
Another suggestion is more far-reaching. One diplomat in London in close touch with daily developments said: ''What's needed now for greater stability in oil prices is a consortium consisting of producers and consumers.
''It could get together to arrange prices, and production quotas, and adequate buffer stocks to iron out price fluctuations.''
Consortia of this type already govern world markets in sugar, rubber, and tin.
The diplomat and other sources in the City of London financial district agree that while lower oil prices are good for the world economy, prices that drop too fast endanger producers, stop investment in oil substitutes and new exploration, and set the scene for another price rise when demand picks up again.
British analyst Anthony Sampson, author of a widely read book about the major oil companies called ''The Seven Sisters,'' agrees.
Mr. Sampson believes that producers such as Mexico, Nigeria, and Venezuela could be bankrupted on the way down. Consumers such as Brazil, South Korea, or India might be hard-hit on the way up.
He sees a strong case for consumers to become involved in stabilizing oil prices - which in the present context means stepping in to stop them from soaring up again after the fall now underway.
Another prominent oil analyst in London feels that the debate over OPEC's future is, for the moment, academic.
In an interview, he said, ''The basic problem is volume. OPEC has to keep production down to keep the price up. But Nigeria and Iran won't cut.
''Let's say they walk out of OPEC. What can the other 11 members do if those two keep on pumping all they can and selling at large discounts?
''With demand so low and hardly anyone buying oil while the uncertainty lasts , OPEC has run out of power for the moment. The longer it keeps talking, the less credibility it has.''
As OPEC met again in London March 13, sources close to the ministers were saying that agreement had been reached on a new OPEC reference price for oil ($ 29 a barrel) with high-quality Nigerian, Libyan, and Algerian oil set at a $1 premium ($30).
However, after a week of almost nonstop meetings, four members were still refusing to accept production quotas outlined by other members.
Iran (fighting Iraq) wanted a high quota, Saudi Arabia (helping Iraq) wanted 5.5 million barrels per day (b.p.d.), Venezuela (with about $28.5 billion of foreign debt) wanted 1.8 million b.p.d., and the United Arab Emirates 1.2 to 1.3 million b.p.d.
Time was running out. Non-OPEC members Mexico and Britain, and major oil companies such as British Petroleum, were impatient for decisions, sources reported.
Mexico, with external debts of more than $80 billion, had promised to delay any price cut of its own while OPEC met. But Mexico has reportedly told OPEC member Venezuela that it will have a statement ''soon.''
Unless Britain cuts its North Sea price yet again, it will lose markets to Nigeria, which matched the British cut by going 50 cents a barrel lower last month.
Nigeria and Britain are particularly keen competitors for buyers in the United States.
Many analysts feel that even if OPEC ministers do patch together an agreement now, it cannot prevent a further wholesale drop in oil prices.
BP, one of the largest oil companies of them all, said as much in a controversial statement issued March 10. The statement angered OPEC ministers, sources reported, and led to a placatory statement from British Energy Minister Nigel Lawson.
Mr. Lawson, however, still refuses to enter into any price or production agreement with OPEC, whose ministers began meeting here in the first place to try and pressure London into just such a pact.
The Thatcher government, which is to announce its budget March 15, is reluctant to trim prices again. It earns (STR)10 billion ($15 billion) a year from taxes on the 2.1 million b.p.d. the North Sea produces.
So far its $3-a-barrel cut has been offset by the dollar's rise in value against the pound, but further cuts will reduce London's oil income in sterling as well, even though the pound is at new lows.
The government wants to cut other consumer taxes in a preelection move, and oil companies are clamoring for tax relief as well. Yet oil prices will have to go down again soon to retain markets, analysts believe.
Nigeria has vowed to match and outdo any British cuts. Such competition would push down spot market prices and an all-out price war is considered a definite possibility.