President Carter and Soviet Foreign Minister Andrei A. Gromyko sharply disagreed over African policy yesterday, but the Russian diplomat expressed hope that the discord would not derail completion of a new nuclear arms limitation pact.

A public clash - more severe than strategists on either side anticipated - developed after Gromyko emerged from four hours of discussions at the White House, sounding relatively opptimistic about the grinding strategic arms limitation talks (SALT).

When reporters turned the questioning to African issues, however, Gromyko said:

". . . Of course we do have differences, and I think . . . that the information which the president has at his disposal is not correct - that is our assessment . . .

"We have no intention of grabbing either the whole of Africa or its parts. We don't need it."

White House press secretary Jody Powell firmly countered, after consulation, that "the president wishes to make it completely clear that that there is no doubt in his mind about the accuracy of the information which he has received and which he has conveyed publicly to the American people and privately to the foreign minister."

Powell was referring to Carter's statements in his Chicago press conference on Thursday that Marxist Angola "must bear a heavy responsibility for the deadly attack" into Zaire's copper-mining Shaba Province, and the responsibility is "shared by Cuba." The Carter administration has charged that Cuba trained the invaders, who were armed with Soviet weapons. Carter added onThursday that unless the Kermlin leaders "show some constraints" in Soviet-Cuban actions in Africa, that could "make it much more difficult to conclude a SALT agreement . . . "

Secretary of State Cyrus R. Vance, with Gromyko at his side at the conclusion of talks at the State Department yesterday, said somberly:

"I feel I must take exception to the statement that was made [by Gromyko] following the meeting with the president this morning, where it was indicated that the president did not have accurate information with respect to the situation in Africa.

"That is not the fact. The president is fully and accurately informed, and I want to make this very clear."

Gromyko, asked at the same time if the United States and the Soviet Union are on a confrontation course over Africa, replied:

"I would not think that that should happen. Both sides should [an American said the Russian word Gromyko employed was more precisely translated as "must"] conduct themselves in a responsible way in that area of politics as well.

"I would add to that, that there is information - and information. And sometimes conclusions are drawn from incorrect and inexact information. And that is bad."

Closing the exchange, Gromyko added, with a strained chuckle to reporters, "And please don't involve me in any more politics," as he waved off the press, saying genially in English, "Goodbye, ladies and gentlemen."

Vance announced that another meeting with Gromyko will be held in New York Wednesday "to carry on discussions." There had been no earlier hints of such a meeting.

This sudden scheduling has all the diplomatic earmarks of a damage-repair meeting to try to soften the sting of yesterday's encounter. It will require Vance to break into the schedule of a major summit conference for heads of government of the 15-nation North Atlantic Treaty Organization, which opens here Tuesday.

Vance said the Wednesday meeting "would be more on the political side than on the technical side" of the nuclear arms control talks.

While Gromyko did his utmost to sound upbeat about the nuclear portions of yesterday's talks, saying they helped to "narrow down the differences" and produced "some headway on some parts of some of the questions," the attitude on the American side was generally gloomy.

Gromyko said the Soviet Union initiated "certain proposals and suggestions" to try to break the impasse on unresolved points in the four-year-old negotiations, and "we - the Soviet Union, the Soviet leadership in general - are certainly in favor of an agreement."

"We certainly stand for peace in general, and for peaceful relations with the United States . . . ," Gromyko stressed.

Vance, however, bluntly said to reporters immediately after his farewell to Gromyko that "I can't say that we made much progress today, but we have to keep at it . . . "

Asked if the latest Soviet suggestions can overcome the remaining barriers for concluding a new limitation on intercontinental missiles and bombers, Vance said Gromyko "did make some new proposals" and "some of them were substantive . . . "

But Vance hardly sounded optimistic. He said, "We've got to take a look and see what these suggestions are that are on the table."

Disappointment clearly registered at the White House after the talks, which began there at 8 a.m. and continued to 12:15 p.m. with a brief interruption for Carter to chat with Rose Kennedy, mother of the late president John F. Kennedy, and to introduce Gromyko to her.

Powell told reporters "the discussions were full and very frank" - a diplomatic euphemism to signify blunt, or tough talks; he repeatedly employed the symbolism "frank" or "very frank."

The discussion, he said, "covered a number of important issues, including SALT, comprehensive test ban [meaning a ban on all nuclear testing, which would seal off the underground testing permitted by the Soviet Union and the United States since their above-ground testing ban in 1963], Africa and human rights."