The deadline President Carter set a month ago for withdrawal of Soviet troops from Afghanistan passed today, unheeded by the Soviet Union. The administration said consequently the United States definitely will not participate in this summer's Olympic games in Moscow.

"The decision is final and irrevocable. We will not be participating in the Moscow Games," State Department spokesman Tom Reston said in Washington, echoing a statement made by his superior, Hodding Carter, in Bonn, West Germany.

Officials of the U.S. Olympic Committee (USOC) confirmed receipt of a letter from the president, dated Feb. 15, advising them of his decision that a U.S. team should not compete in Moscow this year.

However, USOC officials continued to say that they will try to keep their options open, in the event of a later Soviet withdrawal from Aghanistan, and will take no formal action on their invitation to the Moscow Games until after the USOC House of Delegates meets in Colorado Springs April 11-13.

"We are trying to keep the door open because some of our athletes have trained all their lives for this one chance to be in the Olympics, and if the national security isn't involved when the time comes, why shouldn't they go to Moscow?" said USOC president Robert J. Kane.

"The president said at the outset that he was calling on us not to participate because the national interest was in jeopardy. If he decides it is still in jeopardy at a later time, we will abide by his decision.We are not going to defy our president," Kane said.

"But if the situation in Afghanistan changes, I'm sure the president will change his mind and the American people will change their minds. Why would they want to punish our athletes if it's not absolutely necessary?

"Public opinion is bound to swing around if the proposal made by the Common Market nations yesterday is adopted, Soviet troops move out, and Afghanistan becomes a neutral country and decides its own future," Kane went on, referring to a plan emanating from a meeting of nine European Economic Community ministers in Rome on Tuesday.

"If the Soviets want to get out of this situation and see this solution as a way of saving face, how is national security at stake then?" Kane wondered.

However, White House counsel Lloyd Cutler said today that the president's decision against American participation in Moscow is "Final and unequivocal," and that the USOC already has agreed to accept it.

On Feb. 14, the USOC issued a statement saying it would "accept any decision concerning our participation in the Games the president makes in view of his analysis of what is best for the country." Formal action was deferred until the April meeting of the 450-member House of Delegates, the USOC's largest and most representative policymaking body.

"The USOC has legal procedures which, in the opinion of their counsel, have to be followed, and we're not making an issue of that," said Cutler, who met with USOC officials here last weekend and spoke with them by phone Tuesday evening to repat the president's decision.

"We asked them to act promptly" to decline the invitation to Moscow "and they indicated to us that April 11 was as promptly as they could act," Cutler said. "They have to construe their own constitution and bylaws. We are satisfied with their statement of Feb. 14 that they will, of course, comply with the president's request."

Kane said the USOC's 23-member administrative committee will meet March 15 in Colorado Springs and probably will draft a recommendation on Moscow to be sent out with the notice of the House of Delegates meeting.

John B. Kelly Jr. of Philadelphia, first vice president of the USOC, said today the Administrative Committee's resolution "may have some 'outs' in it" -- contingencies for various actions depending on world conditions on May 24, the final deadline for responding to invitations to the Moscow Games.

"We might condition our decision on pulling out of Moscow on the world situation and try to hold off until May 24, when entries are actually due," said Kelly. "But it is pretty well decided that if the president directs us not to go, rather than requests that we not go, we will do as he directs. Right now, he is directing us."

The president has no legal authority to force his decision upon the USOC, but some USOC officials have said they would welcome an order from the White House that would take the onus off them for not participating in Moscow.

Others believe that heeding a direct order would put the USOC in violation of International Olympic Committee (IOC) rule 24c, which states that national Olympic committees must be autonomous and must resist all political pressures.