Egyptian President Anwar Sadat hinted yesterday that something was about to be done to improve Egypt's relations with the Soviet Union, strained for several years after Egypt expelled Soviet military advisers in 1972 and abrogated a friendship treaty last year.

Sadat announced that "a new development will occur in Egyptian-Soviet relations and Deputy Prime Minister and Foreign Minister Ismail Fahmi will announce the news before the People's Assembly" today.

The announcement was made at a news conference Sadat held with Romanian President Nicolae Ceausescu, whose talks in Cairo touched on Egypt's toubled relations with Kremlin.

"Despite the coolness in our relations with Sovie Union and despite the problems we have faced, I wish to say that, regarding the solution of the Middle East crisis, therhas never been any difference at all," Sadat added.

Israel's acting prime minister, Shimon Peres, meanwhile, expressed satisfaction with assurances by President Carter that Israel will receive special treatment from the United States in weapons supply.

"I'm satisfied with the statements and decisions that were taken by President Carter that are continuing the special Israeli-American relationship," Peres said in an interview on Israel state radio.

Israel Foreign Minister Yigal Allon returned from his London meeting with Secretary of State Cyrus Vance in a better mood than he was when he left Israel, officials in Jerusalem said, according to Washington Post correspondent H.D.S. Greenway.

The better mood resulted from both the U.S. assurances about continued preferential treatment for Israel and American reassurances that Washington had not changed its position on the Palsteine Liberation Organization, the officials said.

Although Allon went to London to be briefed on Carter's talks with Arab leaders, he was more concerned about Israel's realtions with the United States, officials said.

From what the Arabs reportedly told Carter, Allon thought there had been progress toward arriving at a definition of peace that could be acceptable to the Israelis and the Americans. There was also reportedly some slight progress on the issue of Palestinian representation because Arab leaders had talked more about a solution involving Jordon - which Israel favors. But the issue was still obbscure, officials said, because the Arabs had not been united or clear on the issue.

In Carter's talks with Arab leaders, there reportedly was no progress at all on the question of Israel's borders, however, according to the officials.

Isreal and South Africa have concluded two important scientific and technological agreements for closer cooperation, according to South Afria's Council for Scientific and Industrial Research.

The announcement, contained in the annual report of the Council, gave few details but said the agreements were "the beginning of a new phase of co-operation between the two countries."

Meanwhile, the chief of the Jordanian royal court said that Jordan, Egypt, Syria and Saudi Arabia will hold high-level talks next month. There was no indication of the purpose of the talks.