The Soviet Academy of Sciences said today that Andrei Sakharov, one of its preeminent members, has ended his hunger strike and that he was in "satisfactory" condition at an unspecified hospital.

The academy's spokesman, Yevgeny Tabakeyev, read a prepared statement that said the Nobel Peace Prize laureate and his wife, Yelena Bonner, have stopped their protest and that they are now subjected to a "special diet for a few days" before they could return to "the normal regimen of eating."

The Sakharovs are given constant medical attention and "the state of their health is satisfactory," Tabakeyev said. He declined to elaborate or provide other details.

The statement was the first official declaration that the country's foremost dissident and his wife have ended their hunger strike after being told that the government would yield to Sakharov's demand to permit a young woman to travel to the United States to join her husband. He is Sakharov's stepson.

The woman, Liza Alexeyeva, 26, yesterday quoted an official of the KGB security police as saying that she had been granted permission to leave the country. Sakharov had vowed before he started his hunger strike on Nov. 22 that he would terminate the fast only if Alexeyeva was permitted to emigrate.

Alexeyeva, who was summoned to the headquarters of the KGB yesterday, quoted the official, Alexander Baranov, as saying that the Sakharovs were told of the decision Tuesday and that they had stopped their protest. Baranov described the state of their health yesterday as "better," according to Alexeyeva.

Alexeyeva was again summoned to the KGB headquarters this morning and told by Baranov that she could visit the Sakharovs in Gorki Monday. Gorki, a city 250 miles east of here, is the place to which the nuclear physicist was banished two years ago.

Both yesterday and today, Baranov cautioned Alexeyeva that the time of her departure for the United States would depend on her behavior, she said. Alexeyeva said Baranov had specifically mentioned her dealings with Western journalists and statements that "produced anti-Soviet feelings in the West."

The Sakharovs were forcibly hospitalized Friday after going 13 days without food. They were taking only mineral water. Baranov's statement suggested that they continued their protest until Tuesday, when they were presumably assured by people they trust that the government had decided to yield to their demands.

It is believed that Sakharov's colleagues in the Academy of Sciences have played a crucial role in attempts to resolve the impasse. But there has been no reliable information here and the city of Gorki is closed to foreigners.

Alexeyeva told journalists that she had tried to get more information about the Sakharovs, insisting on some proof that they had ended their protest. She quoted Baranov as replying, "I have told you everything I have been instructed to say."

The young woman was visibly distressed earlier today because visa authorities whom she had phoned told her they knew nothing about a permission to grant her an exit visa.

Later tonight Alexeyeva said that she was told to report Friday to a district emigration office with her passport and two photographs and to take along 201 rubles (about $150), the sum normally required from prospective emigres to pay for the visa and other fees.

This appeared to suggest that she would be issued her exit papers within the next few days, possibly even Friday.

Tonight's statement by the powerful Academy of Science appears to confirm indications that the government had decided to make an unprecedented concession to the nuclear physicist to settle the embarrassing crisis quickly.

Friday, the government newspaper Izvestia bitterly attacked the physicist for attempting to turn family problems into a "cosmic crisis." It said there were no legal grounds for Alexeyeva to leave the country.

Sakharov's stepson, Alexei Semenov, is a graduate student at Brandeis. He married Alexeyeva in a proxy ceremony in Montana last summer. The Soviet Union does not recognize such marriages. Moreover Semenov's wife, Olga Levchina, and their child joined him in the United States 18 months ago under a "family reunification" provision. Semenov and Levchina have since divorced.

Although some diplomats here expected more bureaucratic complications in the coming days, it is believed that Alexeyeva would soon leave the country. Most likely, she would be given an exit visa to Israel and depart for Vienna, where she would be given a visa for the United States.

It remains unclear, however, how the authorities plan to deal with the Sakharovs, although both were expected to stay in a hospital for some time. He is 60 and she is 58. What damage the protest had done to their health is not known.