Nelson Mandela, the president of South Africa and among the planet's foremost moral authorities, gave President Clinton the kind of emotional endorsement Wednesday night that he has trouble getting these days from members of his own party.

At a White House reception, Mandela said that the domestic debates of the United States were not his business but that his personal code did not allow him to desert a friend. He said South Africa, Africa and the entire world supported Clinton."We do wish to say that President Clinton is a friend of South Africa and Africa," he said, "and, I believe, the friend of the great mass of black people, and the minorities and the disabled of the United States."

Saying that "we are thinking of you in this difficult and discouraging time in your life," Mandela recalled receiving a telephone call two days ago from Frederick Chiluba, the president of Zambia.

"He said, `Mandela, I want you to support President Clinton,' " Mandela said. "He was not speaking for himself, and he said so. He said, `I am speaking for the continent of Africa.' "

Clinton, clearly moved, smiled during Mandela's remarks and appeared at one point to wipe away a tear.

Mandela was repeatedly interrupted with applause from an audience of black religious leaders, presidents of historically black colleges and members of the Congressional Black Caucus. Black Americans have been among the Clinton's most loyal supporters.

By the time Mandela again said he would not "interfere in the domestic affairs of this country," his audience was laughing, convinced that he was doing just that.