The Cuban government encouraged planes from the United States to fly in for pickup of emigrants today even as the tide of small boats coming for the same purpose reached flood stage at a port just west of here.

Today's official Granma newspaper announced on page one that American aircraft could land at the airport in the resort of Varadero, 90 miles east of Havana.

"One U.S. plane already landed yesterday at Havana airport," the paper said, and its pilot was informed that the airlift could proceed from Varadero, " provided this was done in an orderly fashion and planes sent advance notice."

The announcement came in apparent response to yesterday's declaration by the State Department "in support of an international solution" and calling for the resumption of refugee flights "to Costa Rica and other countries."

[a State Department spokesman said the statement was not intended to invite establishing an airlift to the United States].

While Cuba seemed to approve of an air bridge, it did not specify whether it welcomed only private planes or also officially organized U.S. flights.

During the last great exit of Cubans in 1965, Cuba similarly permitted both boats and planes to pick up emigrants here, with the planes using Varadero. Today's statement did not mention the unexpected flight yesterday of a Costa Rican plane allowed to carry 107 Cuban dissidents to San Jose

Today in its daily progress report of the refugee exodus, Granma said that by late last night, 349 American vessels had arrived in Cuba and that 575 refugees left Cuba yesterday. It put the total number of departures since Monday at 1,483.

Dozens more little boats could be seen arriving today, following the coastline between Havana and the port of Mariel to the West, for the pickups. The boats milled about among large Cuban cutters and freighters from the Soviet Union delivering their goods here.

The departure operations here are controlled and subdued.

At Mariel, the hundreds of American boats wait their turn outside at sea and inside the bay. Only about a dozen at a time up at the boarding area. The refugees arrive on government buses, get off almost next to the boats and, on the whole, board quietly.

So far there appear to be three categories of persons leaving:

The 10,800 who stormed the Peruvian Embassy three weeks ago and were given passports or other exit papers.

Those who already had Cuban exit papers but were waiting to be processed by the U.S. Embassy. Many of them are former prisoners and their families. Although official estimates on the number of such people vary, they are believed to be more than 6,000 and perhaps as many as 13,000.

People who are picked up by official bus and taken to the port after the ship captains, often Cuban exiles, ask for them. Well-informed sources said that in the third group, which is very large, men of military service age might have difficulty leaving.

Although there is no commotion on the surface, thousands of would-be refugees are believed to be waiting at home in suspense.

Many people are known to be afraid to express their feelings for fear of provoking the fury of militant supporters of President Fidel Castro in their neighborhoods. At times their emotions come to the surface at the downtown telephone and cable office. A woman who had waited in line for six hours for a cable form wrote with trembling hand to here sister "Lidia, send me a boat. Urgent, please."

All over Havana, signs have been up, pictures of garbage cans and of insects, alluding to the refugees. The signs are distributed via the local Committees for the Defense of the Revolution, which act as watchdog committees on every block.

Another sign is an earlier phrase of Castro, now appearing more frequently, that says "building socialism and communism is a voluntary task."

In the Embassy of Peru, according to charge d'affaires Armando Lecaros, there were only between 900 and 1,000 people left today. The numbers were dwindling rapidly he said as people gained faith in the government promise that they could leave and have taken exit papers home for the vigil until transport is provided them.

The newspaper Granma, which takes its name from the yacht that brought Castro from exile in Mexico 24 years ago, has gleefully run stories of chaos and anger about the improvised rescue operation in the United States.

In a commentary, it scoffed at U.S. threats against boatowners bringing in "illegal aliens." In reference to at least five occasions last year when Cubans here hijacked boats to flee to a warn U.S. reception, the paper asked: "Why do they admit those who use force, hijack boats, take hostages, and why not those who want to go peacefully (with exit documents)?"

The official Cuban position has also been that Venezuela and Peru are responsible for the embassy break-ins, arguing that if people force their way into an embassy, they are granted asylum, but if they ask for visas peacefully they are refused by those countries.