At a secret, high-level meeting in Warsaw during early November 1981, a very agitated Soviet official announced to members of the Polish government and general staff that plans for the upcoming crackdown on the Solidarity trade union were somehow inexplicably leaking to the United States, according to informed sources familiar with U.S. intelligence reports. Everyone at this session voiced dismay, even outrage at the betrayal of such state secrets.

Polish Col. Wladyslaw Kuklinski, a senior staff officer involved in planning the martial law crackdown, joined in, expressing particular shock and distress, the sources said. He then left the meeting and gave a prearranged emergency signal to the Central Intelligence Agency station in Warsaw. Within hours the colonel, his wife and at least one son were "exfiltrated," the CIA tradecraft name for the undercover extraction of agents in danger.

Kuklinski had been a longtime human asset of the CIA who provided such superior intelligence about the planned crackdown and forthcoming imposition of martial law that the White House had "the operational blueprint," one U.S. source said. At one point, the source said, these plans were on President Reagan's desk.

In an interview in Warsaw yesterday with a Washington Post correspondent, Polish government spokesman Jerzy Urban volunteered information about the case, including naming Kuklinski and stating that he had been deeply involved in planning for martial law.

Urban said Kuklinski had been a CIA spy on the Polish general staff and claimed that the Reagan administration could have prevented the imposition of martial law the next month, December 1981, by making public the then top-secret Polish intentions.

"The U.S. administration could have publicly revealed these plans to the world and warned Solidarity," Urban said. "Had it done so, the implementation of martial law would have been impossible."

The Polish decision to disclose hitherto secret details about Kuklinski, including revealing his name publicly for the first time, appeared designed to bolster the Warsaw government's contention that Reagan failed to do all he could to help Solidarity and was not interested in a peaceful solution to the Polish crisis.

U.S. sources denied that this would have been possible because, according to their account, the only key fact Kuklinski had been unable to provide was the date the Polish government planned to impose martial law.

The CIA considered the penetration of the Polish high command to be among their most important intelligence successes. Over a period of time, Kuklinski had provided stunning, timely information on various plans from the highest levels of the Polish government and general staff, U.S. sources said, but in the past some of those plans had never been executed.

"We had everything in the plan but the day," one U.S. source said, "and therefore there was no way to act."

But Urban, in the interview, said that Kuklinski was aware that Dec. 15 was a deadline for the implementation of martial law since large numbers of conscripts were due to be discharged from the Army at that time.

The declaration of martial law on Dec. 13, 1981, by Poland's military leader, Gen. Wojciech Jaruzelski, effectively ended the first experiment in trade union pluralism in a communist country.

Kuklinski and his family now live in the United States under new identities, according to two U.S. government sources. One of them described Kuklinski as "a very brave man who became an agent [for the CIA] not for money but because he detested what the Soviets and [Polish] military government had done to his country."

The source said that Kuklinski was convicted in Poland of espionage and the death sentence was imposed in absentia.

Kuklinski was able to provide the CIA with a copy of the final operational plan for the crackdown on Solidarity, according to U.S. sources. Copies of this plan, which did not have a date for implementation, were printed in the Soviet Union so that as few Poles as possible would know about it, the sources said.

On Dec. 23, 1981, in a televised speech on the crackdown in Poland that had taken place 10 days earlier, Reagan said: "It is no coincidence that the martial law proclamations . . . were being printed in the Soviet Union in September." At the time, some former intelligence officials and other experts suggested that Reagan's remarks were an unusual breach of official secrecy.

Urban yesterday said that Kuklinski knew such details as lists of internees, movements of Polish Army units, and the preparation of anti-Solidarity legislation to accompany the state of emergency.

As the one condition for speaking on the record, Urban insisted that The Washington Post should ask the U.S. administration about his account of one of the most mysterious episodes in the entire Solidarity drama.

The White House had no immediate comment last night.

The meticulously planned crackdown, which was accompanied by the internment of an estimated 5,000 union activists, followed 16 months of gathering tension between Solidarity and the Communist authorities.

Urban said the Polish authorities first became aware that Kuklinski was a U.S. agent when he failed to report for work on Nov. 6, 1981. His house, and the houses of his two sons, were found to be empty.

According to Urban, the Polish authorities assumed that the CIA had decided to "withdraw" Kuklinski along with his entire family from Poland in order to be able to reveal his information on the preparations for martial law without jeopardizing his safety. Urban said it was believed in Warsaw that Kuklinski was safely in U.S. hands from Nov. 7.

"The Polish authorities waited for some kind of announcement from Washington. But time passed and the United States was silent, so the plans were put into effect," Urban said. He described Kuklinski as "an operational officer in charge of planning martial law" on the Army general staff, but would not give his exact position.

Urban's version of the Kuklinski case differed sharply with a fragmented account that appeared in Newsweek magazine in December 1982, reportedly drawn from U.S. sources. According to the Newsweek account, which did not name the agent, the Reagan administration was unable to warn Solidarity about the imminence of martial law without putting the colonel's life in jeopardy. This claim was dismissed by Urban today as "nonsense."

His own analysis of the reasons for Washington's silence, Urban said, was that the Reagan administration appeared to believe that the imposition of martial law would result in a "bloody conflict" in Poland that the United States had no interest in preventing. He said that Reagan later became very angry at the ease with which Solidarity was crushed.

"This incident gave us an insight into Reagan's actions and sayings. Much of the love which he professes for Solidarity is insincere. He could have prevented the arrests and internments, but did not," Urban said.

The disclosure by the Polish government of an incident that would normally be hushed up by a communist country appeared to result in part from continuing political strains between Warsaw and Washington. Urban accused the Reagan administration of continuing to take a hostile attitude toward Poland by receiving exiled Solidarity leaders and expressing support for the Solidarity underground.

Asked why the information had not been disclosed beforehand, he replied: "It is not an easy or pleasant matter to reveal that the Americans had an agent so high in our headquarters or that a Polish colonel was an American spy. We were patient and had hopes that things could be worked out" between Washington and Warsaw.

Urban said Kuklinski was present at a high-level planning meeting for martial law a couple of days before his disappearance and was therefore particularly well-informed. The meeting was also attended by heads of all Army and government departments involved in the preparation of the highly secret operation, the existence of which was known only to a handful of people close to Jaruzelski.

The maintenance of strict secrecy was a key element in the success of the Polish government's plans to suspend, and eventually outlaw, a massive social movement that numbered an estimated 10 million members by late 1981 without large-scale loss of life. Solidarity activists were caught completely by surprise when special police units began the mass arrests in the early hours of Dec. 13.

Besides raising questions about the Reagan administration's handling of the crisis, Urban's account also provided official confirmation that plans to implement martial law were well advanced by November 1981. Previously, Polish spokesman had insisted that the crackdown was a last-minute decision motivated by a call by Solidarity for street protests on Dec. 17.