The Reagan administration, defending itself against criticism of its attempt to organize an international boycott of Beirut airport, said yesterday that it was only trying to find "an effective way" to deal with the security problem there and not seeking to harm Lebanon or its airline.

"It should be clearly understood that the objectives in bringing the problem of Beirut airport to the attention of the international community is not to try to punish Lebanon or Middle East Airlines," the White House and State Department said in a prepared statement.

"It is, rather, an urgent appeal to all who have a stake in the safety of international civil aviation to find an effective way to deal with a severe and persistent security problem at Beirut airport."

Despite escalating rhetoric denouncing terrorism, the boycott is the only concrete action the administration has taken so far in retaliation for the June 14 hijacking to Beirut of Trans World Airlines Flight 847 and the subsequent taking of 39 American passengers as hostages for 17 days. But the United States has had great difficulty in gaining support for its action from European and Arab allies.

The U.S. defense of its boycott action came after sharp Lebanese and other Arab criticism of the decision last Monday to stop Lebanon's state-run Middle East Airlines (MEA) and its private cargo carrier, Trans Mediterranean Airways, from landing in the United States as part of its diplomatic drive to isolate the Beirut International Airport.

On Friday, Lebanon asked the Arab League to convene a meeting of aviation ministers to discuss a Lebanese government request that Arab nations retaliate "on the basis of reciprocity," according to Lebanese Ambassador Abdallah Bouhabib.

Lebanon wants the Arab countries to boycott the two U.S. airlines flying to the Arab world, Pan American World Airways and Trans World Airlines, in retaliation for the U.S. action against MEA.

"We're going to ask that Arab governments take retaliation on the basis of reciprocity," Bouhabib said. "You're putting all your [Arab] friends on the spot."

None of America's European or Arab allies has followed the U.S. example of cutting off MEA flights, although Prime Minister Margaret Thatcher said last week that Britain would do so, "provided we can get all the Bonn summit countries to stop them."

The seven summit nations -- the United States, West Germany, France, Italy, Japan, Canada and Britain -- set up a special committee to deal with terrorism at their first meeting in July 1978. Washington is expected to formally propose its steps to isolate the Beirut airport at the committee's next scheduled meeting in Bonn July 23.

Administration spokesmen Larry Speakes and Edward P. Djerejian were unable to answer reporters' questions yesterday about what cooperation had been forthcoming from U.S. allies for action against Beirut airport and Lebanon's air cargo and passenger lines. Both said that "consultations" were continuing.

At one point, Speakes appeared to back off from U.S. determination to close down the airport, saying Washington was still committed "to what we can get our allies to help us to do." But he reiterated that the goal remained the same of getting "the airport -- the mess surrounding the airport -- cleaned up."

He said the steps taken by the Lebanese government over the weekend to improve security at the airport, including earthen barriers to narrow access to it by the various militias, were "welcome but they're not yet sufficient."

Vice President Bush was in Paris last week when the administration announced the boycott but never brought up the specific U.S. proposal with French leaders then, according to a French Embassy spokesman.

An aide, Marlin Fitzwater, confirmed that Bush's conversations in Paris had been limited to a general discussion of allied cooperation in combating terrorism and that no formal request for French support of the U.S. boycott of the Beirut airport had been made.

A State Department spokesman said, however, that a formal request had been made "at a high level" to the French government after Bush's visit and that other U.S. allies have also been presented with the U.S. proposal.

In a resolution passed at the first Bonn summit of the six major western powers and Japan in 1978, the seven nations pledged to "take immediate action to cease all flights" to any country that refuses to extradite or prosecute a hijacker or does not return the hijacked aircraft.

They also agreed to "initiate action to halt incoming flights from that country or from any country by the airlines of the country concerned."

At least on paper, then, the seven are committed to a similar line of action to punish a nation like Lebanon that appears to have neither the political will nor the military capability to arrest and try the two original hijackers, or extradite them.