U.N. Ambassador Andrew Young said yesterday that congressional constraints have not hindered the Carter administration's efforts to provide limited aid to Zaire and other nations fighting communist-backed troops in Africa.

"I don't agree that the president's hands are tied," Young said on "Face the Nation" (CBS-WTOP). "I think there's enough support of the president in this country and in the Congress for us to openly do anything we want to do in Africa."

Indeed, the United States is in a better position in Africa than it was a year ago because it has been exercising caution in countering the Soviet-Cuban intervention, Young said. "I think the slowness to respond has been very much in our favor," he said.

Young's comments seemed to conflict with those of President Carter, who complained to congressional leaders last week that restrictions on emergency U.S. assistance to friendly foreign countries hampered the administration's efforts to aid nations like Zaire, which has been attempting to repel a border-crossing force from Angola, where there are an estimated 20,000 Cuban troops.

Also, in a meeting Friday with American editors, Carter complained of having to operate under "very tight constraints" to use limited aid to counter Soviet-Cuban involvement in the African conflicts.

Young was asked if he was "somewhat out of step with the drift of what is being said . . . by the administration."

"Well, I'm out of step with what's being reported in the press about the administration," he replied.

Young said that in his conversations with defense, Central Intelligence Agency and State Department officials on U.S. African policy, he did not find "the panic that one reads in the press."

"I think we're much more confident of our Africa policy" than is publicly conveyed, he said.

Asked about Young's remarkss, White House deputy press secretary Rex Granum said only, "The president's views on the issue of restriction remain as he has previously expressed them."

Young also said he would not favor the repeal of an amendment restriction covert U.S. activities in Angola. That amendment, sponsored in December 1975 by Sen. Dick Clark (D-Iowa), bars direct or covert U.S. assistance to Angola without congressional approval.

"I think that the history of clandestine reactions and activites [shows that they] have clouded the conduct of foreign affairs and have not really worked anywhere," Young said. If the president "has the desire to do" any more than the United States is now doing in Africa, "I think he can get the support from Congress to do that," the ambassador said.

Increased U.S. influence in Africa is assured if the United States maintains a "steady, quiet approach" and continues to be "constructive" and "thinking" in dealing with communist-led insurgencies on the African continent, Young said.

"I would be absolutely certain that, in 10 years, our relationships - even in Ethiopia and Angola - will be better than will be the relationships between those countries and the Soviets or Cubans," he said.

Present Cuban military involvement in Africa will undercut any gains in influence Cuba may now have on the continent, said Young, who once said that Cuban troops in Africa were a stabilizing force.

In the territorial disputes in Ethiopia over Eritrea and the Ogaden Desert, "there is some evidence" that the Cubans "are gradually being sucked more and more into military involvements," Young said. "Insofar as they attempt to solve the problems of Africa military, they are definitely a destructive force."

But, he cautioned, "I don't think it's right for us to become a destructive force because they are a destructive force."

Young also warned against linking the outcome of the U.S.-Soviet strategic arms limitation talks to Soviet-Cuban actions in Africa.

"I would be very cautious about that," he said. "I don't think it's in our interest, because of adventures that we oppose in Africa, to make a linkage which would require us not to sign a strategic arms limitation treaty."