Iran yesterday reiterated demands that the OPEC cartel cut back on exports, but the statement isn't expected to have a serious impact on the United States or other western oil-importing nations.

Calling for a drop in exports, Iran's oil minister, Ali Akbar Moinfar, said the organization of Petroleum Exporting Countries output "is far too high and has to come down and reach a rational level."

But international oil analysts say that even if OPEC members do follow through with some of their individually announced cuts in oil exports, it isn't likely to force a server shortage in the United States or elsewhere.

"The big question is still Iran -- not just cutbacks -- but whether Iran just collapses altogether, shutting off exports," said Thomas Peake of Standard Oil Co. of California. "Barring that, we don't see a serious problem next year."

Today the cartel is exporting slightly more than 31 million barrels a day. But International Energy Agency officials in Paris warn that a drop in exports to as low as 28 million barrels a day could create a shortage in the industrialized nations.

At the Petroleum Industry Research Foundation in New York, John Lichtblau agrees, adding that a cut to 28 million barrels a day is "unlikely. But if we went substantially below 30 million barrels a day for a long period, it would create problems," Lichtblau said.

But because most industrial states' oil stocks are brimming, oil executives say the small cutbacks in exports likely to take place won't bite into available supplies. Japan, for example, has record inventories equal to more than 100 days' consumption, and the United States is within 65 million barrels of its historic 1977 peak level.

Aside from another convulsive outbreak of fighting in Iran that could choke off its exports altogether, White House, State Department and oil industry officials worry most about a sharp cut in Saudi Arabia's exports.

"The big uncertainty could be Saudi Arabia," warned Walter J. Levy, a petroleum consultant.

In recent weeks, aides to Secretary of State Cyrus Vance have advised him that the political turmoil in Iran could spill over into the other Persian Gulf states, forcing oil cutbacks in Saudi Arabia and elsewhere.

Since July, the Saudis have been exporting 9.5 million barrels a day, one million more than their 8.5-million-barrel-a-day production ceiling. During his visit last week to Saudi Arabia, Treasury Secretary G. William Miller was unable to win a public commitment from Riyadh that the Saudis would hold production at existing levels during the first quater of next year.

But executives at some of the Aramco (Arabian American Oil Co.) parent companies -- Exxon, Social, Texco, and Mobil -- say they expect the Saudis to keep producing 9.5 million barrels a day through the first months of 1980.

Some cuts in OPEC exports are already in the works, however, but analysts such as Lichtblau and Peake say they are based more on "technical than political reasons." The cutbacks:

Yesterday in Paris, Venezuela's oil minister, Humberto Calderon Berti, said Caracas would reduce exports by 150,000 barrels a day beginning Jan. 1.

Kuwait's oil minister, Ali Sabah, has said his country may reduce output from more than 2 million barrels a day to 1.5 million barrels a year. Oil-men say, however, that Kuwait recently indicated the cuts are more likely to come later next year.

Abu Dhabi, the leading producer in the United Arab Emirates, has said it would reduce exports by 70,000 barrels a day in January because of technical reasons.

Algeria, OPEC's smallest North Afican state, also plans to cut crude exports by 100,000 barrels a day, but will export the same amount instead as refined products.

Indonesia has said it would cut back exports by 100,000 barrels a day next year, also for technical reasons.

And the Soviet Union has said it will reduce exports to Western Europe by 80,000 barrels a day next year.

Oilmen say there also is a remote possibility that Libya's mecurial leader, Mumamer Qadaffi, might cut back exports as a show of solidarity with Iran, but so far there is no evidence of that.

[meanwhile, Dow Jones News Service reported that major purchasers of Iranian oil are being called to Tehran to discuss their supplies for next year.]

[and the Royal-Dutch Shell group and British Petroleum said yesterday in London that they were invited to discuss supplies this weekend with the state-owned National Iranian Oil Co.]

As a measure of the uncertainty about furture OPEC cuts altogether, Iran's Moinfar has said that Tehran plans a stiff 700,000-barrel-a-day cut -- the same amount sold to the United States before President Carter embaroged Iranian oil. Since Moinfar's statements, through, Iran has continuted to sell most of the 700,000 barrels a day on the spot market, and hasn't dropped exports.