The Reagan administration indicated its strong disapproval yesterday of France's decision to halt all new investment in South Africa, but stepped up its pressure on the white government there by calling on it to move "promptly" away from its apartheid system of racial segregation.

At the same time, the South African Embassy here said the United States had asked for a high-level meeting of officials from the two governments to discuss the current crisis, but administration officials indicated it was only one of several options under discussion.

"I would not eliminate it as an option, but to say we are asking for or planning a meeting, that's not right," said State Department deputy spokesman Charles E. Redman.

Secretary of State George P. Shultz nonetheless hinted to reporters on a flight to Mexico that a meeting might be in the works. "If you want to express a point of view in a direct way, you have to do it directly," he said.

Earlier, White House and State Department officials characterized as "speculative" a report that South Africa had asked for a high-level meeting with the United States somewhere in Europe to discuss the situation.

However, a South African Embassy spokesman said "it seems to be correct" but insisted that the initiative had come from Washington and not Pretoria. The details of when such a meeting would be held, where and who might participate would not become clear until next week, he said.

Meanwhile, Sens. William V. Roth Jr. (R-Del.) and Christopher J. Dodd (D-Conn.) sent a letter to Shultz, strongly opposing any such meeting with South Africa "at this critical juncture," calling it "most unwise and contrary to U.S. interests."

The two senators said such talks would sow discord between the United States and its European allies and be seen as a "severe rebuke" to France and Britain, which came out strongly this week against South Africa's imposition of a state of emergency and crackdown on black dissent.

The administration also criticized more openly yesterday the South African decision to declare a state of emergency to deal with the rising racial violence in that country, but still fell short of openly demanding that it be lifted as Britain did Tuesday.

Redman said that actions such as the French decision Wednesday to halt new investments "both undermines South Africa's economy and creates additional hardships for black South Africans."

The administration has similarly opposed bills passed by large majorities in the Republican-controlled Senate and the Democratic-led House that would impose various kinds of U.S. economic sanctions on South Africa. Thus, the negative U.S. reaction to the French move came as no surprise.

Apparently reacting to steps taken by its European allies in the past three days, however, the administration yesterday stepped up its own criticism of the state of emergency and its calls upon the white-ruled government to change its policies.

White House spokesman Larry Speakes said South Africa "must move promptly away from apartheid, which we find to be repugnant and which is a basic cause for the violence South Africa is witnessing today."

At the same time, Redman said the United States shared its allies' concern over the imposition of a state of emergency "and the potential it holds for abuse which, in turn, could trigger further violence."

Both Speakes and Redman continued to insist, however, that the administration was not contemplating any "review" or "reassessment" of its controversial policy of "constructive engagement," or quiet diplomacy, in its dealings with South Africa, such as a high-level meeting between U.S. and South African officials might suggest.

"We have no plans for a high-level, U.S.-South African meeting in Europe," Speakes said. "In our view, the policy we have laid out towards South Africa and the southern Africa region is the correct one. We are reviewing the situation but we are not doing a wholesale review."