Another group of oil producers - all Latin American neighbors of the United States - is beginning to act jointly to try to hold oil prices as high as possible.
In time it could form a new regional body of oil exporters. Unusually, it would combine two OPEC and two non-OPEC nations.
The first step is a meeting in Caracas Aug. 1 between two members of the Organization of Petroleum Exporting Countries, Venezuela and Ecuador, and nonmembers Mexico and Trinidad-and-Tobago.
Their combined production is a significant 4.8 million barrels per day (b.p.d.), higher than any individual OPEC country except for Saudi Arabia.
''Our immediate purpose,'' said Mexico's deputy energy minister in charge of oil, Eliseo Mendoza Berrueto, ''is to talk about market conditions and to look into technical assistance between all of us.''
However, Mr. Mendoza carefully left open the prospect that a joint regional body could come ''later on.''
Meanwhile, Mexico continues to support OPEC's decision to hold prices and quotas firm at current levels.
However, if OPEC lifts its production ceiling later in the year from the present 17.5 million b.p.d., Mexico would raise its own self-imposed export ceiling from 1.5 million b.p.d., Mr. Mendoza said. Venezuela's OPEC-imposed export ceiling is 1.7 million b.p.d. Ecuador exports about 200,000 b.p.d., while Trinidad-Tobago produces about 100,000 b.p.d.
Mexico is one producing country with whom OPEC is working to cooperate on oil production and prices. Others include the Soviet Union, Britain, and Norway. Mr. Mendoza makes the point that Mexico is close to a number of OPEC members, yet has no formal contacts with OPEC as a body.
With a total foreign debt of almost $85 billion, Mexico relies on oil to bring in 70 percent of its export income. Mexico's total capacity to produce is around 3 million b.p.d., Mr. Mendoza said. This is likely to rise to 3.5 million b.p.d. by 1990.
Exploration had slowed down because of government austerity measures, Mr. Mendoza went on, but he hoped that new spending rules for the state oil company, PEMEX, would free enough money to finance more exploration next year.
One cloud on the horizon: In Mexico's biggest export market, US oil demand is not rising as fast as the rate of economic recovery.
Meanwhile, ''we have a rule,'' the minister said, ''not to be more dependent on the US market than 55 percent of our total of 1.5 million b.p.d. of exports.
''We are developing new markets in Europe right now, though we have rejected bids to buy 250,000 b.p.d. recently to keep under our export ceiling. . . .''
Mexico, he said, fully supports the OPEC decision in Helsinki to hold prices and quotas firm at current levels.
At the same period in past years, world demand had risen in anticipation of winter, but now OPEC has learned not to fall into what Mr. Mendoza called ''this seasonal trap.''
Did he feel that OPEC was in danger of being left behind, since it now produces less than 40 percent of world oil?
''No,'' he said. ''Don't worry about the 40 percent. OPEC is a coherent group of countries coordinating their policies.
''Its self-discipline since its meeting in London in February and March is a remarkable achievement. Many people thought it could not last for more than one month, or perhaps three.
''But it has lasted - a real success.''