The Carter administration's threat to boycott the 1980 Olympics if they are not moved out of Moscow is meeting strong opposition from U.S. and international Olympics committees.

Deputy Secretary of State Warren M. Christopher, who left for Europe Sunday to consult with U.S. allies, reportedly will try to muster support for moving the Olympics from Moscow in protest of the Soviet invasion of Afghanistan.

Many Soviet experts within and outside the U.S. government are advocating a boycott of the games. A boycott, they say, would damage Soviet prestige throughout the world, potentially causing the Soviets more harm than the partial grain embargo already in force.

A boycott or moving of the games would be costly to the Soviets. U.S. intelligence sources estimate the preparations for the games will cost the Soviets $3 billion.

However, Olympic officials -- who in theory operate independently of their governments -- said yesterday it would be impossible to move next summer's games at such a late date. Formal invitations to the United States and 135 other national Olympic committees are scheduled to be sent out in the next two weeks.

National committees have until July to accept or decline. Should the United States decline and then change its mind, American athletes could be barred, under Olympic rules, from the 1984 Olympics in Los Angeles, according to Col. F. Don Miller, executive director of the U.S. Olympic Committee.

Miller said no one in the Carter administration has contacted the committee about boycotting the Olympics, despite statements by President Carter that he opposes holding the Olympics in Moscow if Soviet troops remain in Afghanistan.

"I wonder who in government is considering how to reimburse the dedicated amateur athletes for the many years they have given through self-sacrifice, financial hardships in their attempt to represent our country in the Olympic games," he said. "We should resist political, religious and racial intrusions into the games."

The 82-member executive board of the U.S. Olympic Committee voted Jan. 7 to "resist political intrusion into the games," despite U.S. concern over Afghanistan, Miller said.

Asked if the United States might still field an Olympic team if the administration requested a boycott, Miller said, "That possiblity does exist."

But if the administration took action to prevent participation, such as revoking passports, Miller said the U.S. committee wouldn't "really have any choice in that situation."

The International Olympics Committee (IOC) is adamantly opposed to any change of plans for the summer games. IOC President Lord Killanin said in an interview from his Dublin home, "It would be physically impossible to move [the games] at this stage."

In a separate statement, he said, "Up to this date there are no sporting grounds for the IOC to withdraw the games from Moscow. The IOC reiterates that National Olympic committees can compete or refuse to compete. rIt is up to them. The IOC does not want to interfere with the international affairs of the national Olympic committees."

He added, however, "We would remind that the games are for the athletes, not for the officials or for politicians."

Whether the Carter administration recommends a boycott may depend on what support it receives abroad. So far, the reception to the idea of an international boycott has been lukewarm.

Although Canada has said it favors moving the games from Moscow, and the Netherlands has withdrawn financial support from its athletes, the only country to announce formal boycott is Saudi Arabia.

Olympic officials in West Germany, Italy, Japan, Mexico, Spain, Denmark and Tanzania, said in interviews with Washington Post foreign correspondents this weekend that they oppose political interference in the games.

Other nations, including Britain, Norway, Sweden, Kenya, Thailand and Australia, are taking a wait-and-see attitude.

Olympic officials were also unreceptive to Carter's suggestion that the games could be held in several sites, for example, gymnastics in Japan, boxing in Cuba and field and track events in the United States.

New York businessman Julian Roosevelt, one of two Americans on the International Olympic Committee, said such a move "would destroy the whole idea of the games, which is to bring together top athletes from different sports."

"Any boycott isn't going to change the Soviets' mind and isn't going to get troops out of Afghanistan," Roosevelt said. "I'm as patriotic as the next guy, but the patriotic thing to do is for us to send a team over there and whip their ass."

The second American representative on the international committee, Douglas Roby of Ann Arbor, Mich., said, "I don't think the athletes will go for [a boycott]. I think they would have to be forced not to go. The State Department could refuse to issue passports or visas for them to travel to Moscow, but otherwise I think they would go."

About 10,000 Americans participate in the final U.S. Olympic trials and more than 500 are selected for the U.S. teams. NBC, which has paid $87 million to Moscow for television rights to the games, has said it would withdraw if the United States does not participate. The network carries insurance with Lloyd's of London for 90 percent of that payment should the telecast be canceled.

If the U.S. boycotts the games, Miller of the U.S. committee says, "We are punishing ourselves and using our athletes, who have dedicated themselves to representing the country in the Olympics, as pawns in an international struggle."

However, taking a more moderate stance, Edward G. Williams, chairman of the athletes' advisory committee to the U.S. Olympic Committee, said he doesn't believe "the USOC is going to second-guess what Carter deems appropriate in terms of policy.

"If Carter says, 'Look, boys and girls, you're not going,' then the USOC is hardly going to be the one to say, 'We're going anyway.' There won't be any need to lift [passports]. All he has to say is, 'Call it off,' and the USOC doesn't have any choice."