Iran resumed oil exports yesterday after a brief shutdown Tuesday that sent spot oil prices upwards and touched off a flurry of fears that the nation could again face gasoline lines.

"We understand there was an interruption yesterday, but that the flow is now continuing," State Department spokesman Hodding Carter told reporters yesterday.

Yesterday, Clarksons, a leading London-based tanker chartering company, told its major American oil company clients that two tankers had loaded at Kharg Island, Iran's major oil terminal, by midday. Clarksons also said that four other tankers were receiving oil shipments, and four more were waiting to take on oil. At the State Department, however, officials said that apparently none of those tankers was destined for American ports.

And on Capitol Hill yesterday, Energy Secretary Charles Duncan Jr. told a closed session of the Senate Energy Committee that Iran was again shipping oil, but that the situation remained "fluid."

Duncan said he views the nation's energy future with "real gloom," and although he does not expect gasoline rationing to be necessary, production curbs in such nations as Saudi Arabia, Venezuela and Iraq are likely to put additional upward pressure on prices next year.

Executives at a number of major U.S. oil companies agreed in interviews yesterday that the likeihood of gasoline lines is not great, but they do forsee further rapid price increases.

And indeed news on the pricing front was chilling. Spot prices in Roterdam and on the Gulf Coast, which jumped sharply Tuesday following a Central Intelligence Agency report tha Iran had halted the loading of tankers, continued to climb yesterday. Regular gasoline reached $1.14 a gallon and heating oil 94 cents on the Gulf Coast.

"Spot prices are going wild," said John Buckley of Northeast Petroleum Co.

And many market analysts believe that the Iranian situation could provide the oil cartel with an irresistible opportunity to jack up prices at its December meeting. "Things could not be going worse now for December," said Bruce Wilson of Smith, Barney Harris and Upham.

Wilson said that an increase from the current $23.50 to almost $30 a barrel is not improbable.

Since the beginning of the year, the Organization of Petroleum Exporting Countries has raised its official price from $13.34 a barrel to $23.50 a barrel, the biggest jump since the 1973-1974 oil embargo. Spot prices, those prices charged for a single cargo, however, have continued to run well above official prices in recent weeks, hovering at about $40 a barrel.

International petroleum analyst Walter J. Levy yesterday said, "What Iran will do the the spot market -- heaven help us." Levy said that unless the industrial nations can bring spot prices under control, "there will be another massive price increase."

Yesterday in Tehran a National Iranian Oil Co. spokesman told reporters, "Both the refinery in Abadan and the oil-loading terminal at Kharg Island are functioning. There is no strike; everything is normal." After wards, Tehran's oil minister Ali Akhbar Monifar, said that Iran will continue exporting its oil to the West, including the United States.

CIA reports circulated in Washington Tuesday evening were prompted by an order from the head of the Kharg Island terminal, Iran's leading oil export center, to not load American ships. Duncan told the Senate Energy Committee that this order was reversed by Tehran.

Oilmen such as Conoco's senior vice president, Sanuel Schwartz, though, continue to describe the situation in Rian as "bordering on anarchy." CIA officials say that there is a major question whether Khomeini's radical Islamic goverment has sufficient control over the oil workers at Kharg Island, at the Key Abadan refinery, as well as in the prolific Persian fields.

For example, when Monifar, recently appointed to his post as oil minister, made his first visit to Abadan, a major Iranian oil center, he was set upon by workers angry over a salary dispute. He was hit over the head with a pipe wrench, kicked to the ground, and had to be hospitalized with broken ribs. (Officially he was descirbed as recuperating from a minor heart aliment.)

In the face of this sort of uncertainty, many international oil experts agree with James E. Akins, a former abassador to Saudi Arabia, who said: "No one can really count on Iranian oil in the years ahead."

If oil goes to $30 a barrel early next year, it will add 10 to 15 cents a gallon to gasoline and other fuel costs.

The new round of price increases, inronically, comes at a time when the world oil market has nearly returned to equilibrium. U.S. stocks of heating oil and gasoline are now high, and the International Energy Agency in Paris has said that most industrial nations have sufficient supplies on hand to get through the winter.

In recent weeks OPEC ministers such as Saudi Arabia's Ahmed Zaki Yamani had predicted that the world could face a temporary oil glut next year because of the expected decline in oil demand resulting from the recession.