WARSAW, JUNE 5 -- Solidarity, the famous labor union movement that survived a decade of Communist repression and last year scored the first victory in Eastern Europe's season of revolution, is now at war with itself.

After less than a year as the preeminent political force in Poland, the movement is being crippled with self-inflicted wounds.

The internal conflicts are occurring against the backdrop of plummeting living standards in Poland, a country now squeezed by the most aggressive free-market economic policy in Eastern Europe. As hardship becomes part of an already grim life, many working Poles say that the novelty of a non-Communist elected government is wearing thin.

Solidarity's major asset, a decade-long alliance between workers and intellectuals, is beginning to crumble. The union's leader, Lech Walesa, is the agent of change, as he has been since he was a shipyard electrician in 1980.

In the name of the workers, Walesa has declared "a war at the highest level" against a government that is run by his longtime Solidarity allies. Walesa now derisively refers to these men "as the egghead bastion in Warsaw." They, in turn, grumble that the Nobel Peace Prize laureate is acting like an "absolute monarch."

Walesa, who holds no official position in the government, has announced that he wants to be president of Poland. His advisers say he wants the job by this fall, but Prime Minister Tadeusz Mazowiecki, an editor who was handpicked by Walesa to lead the government, has said that such a change should wait at least until next year.

The loudest volley in Walesa's war was fired Monday when he sent a fax message from his headquarters in the Baltic port of Gdansk to the Warsaw offices of the Solidarity newspaper, Gazeta Wyborcza. In it, Walesa withdrew his support from the paper's founding editor, Adam Michnik, a historian who over the last decade has been perhaps the single most articulate, persuasive and influential thinker in Solidarity.

Walesa said it is "disputable" whether the newspaper, which is the most prominent mouthpiece of the Solidarity-led government, should "still bear the logo of Solidarity." He appointed Michnik to his position last year before the parliamentary elections that led to the downfall of the Communists. But in his message, Walesa said "my nomination has become pointless."

The reasons behind this and a number of other assaults by Walesa on his Solidarity allies, many of whom are longtime friends, range from his insistence that the new government has moved too slowly in sacking holdovers from the Communist past to his claim that the government's free-market program is causing too much hardship for workers.

Last week, Walesa single-handedly headed off a potentially disastrous nationwide railroad strike. That personal victory appears to have emboldened him in challenging intellectuals such as Michnik. But perhaps the decisive reason behind a political battle that is beginning to overshadow all other issues in this country is Walesa's desire to be president.

Some leaders of the government, legislators and editors at Gazeta Wyborcza say they are frightened by this prospect. They accuse Walesa of acting like a demagogue and sabotaging the stable image that Poland must project to continue to enjoy Western support for rebuilding its collapsed economy.

Mostly they criticize Walesa in private. But lately, Gazeta Wyborcza has not contained its irritation.

"This is a man who had integrated the entire society and now is splitting it," wrote Ernest Skalski, the paper's deputy editor. His article said that Western donor countries are coming to the conclusion that Walesa is "destabilizing the political situation in Poland."

Two days before the fax to Solidarity's Warsaw newspaper, Walesa sent one demanding the resignation of another longtime Solidarity activist, Henryk Wujec, who has been unenthusiastic about Walesa's intention of becoming president. But Wujec, an anti-Communist activist since 1976, refused to quit his position as secretary of the Solidarity citizens' committees, which are a key political arm of the movement.

Regional citizens' committees organized Solidarity's huge victories in legislative elections last June and in local elections last month. Indeed, they were far better organized in fielding candidates and getting them elected than the union's own regional offices.

"Thank you very much," Wujec shot back by fax to Walesa. "You see, you are overworked, and perhaps you forgot that I was elected to the post of the secretary . . . and only the committee can recall me."

Within hours, Walesa fired back another fax: "Feel dismissed."

This exchange prompted Gazeta Wyborcza, in an editorial Monday, to publicize what it believes Walesa is trying to accomplish:

"The reason for dismissing Wujec . . . is a purging of the ranks, and he wants to have in important posts and important institutions men who wish to participate in such a war. . . . The way Wujec was fired fits monarchy, an absolute monarchy."

With Walesa out front, Solidarity has become an exceptionally odd political organization. As local elections last month showed, it remains the only group that Polish voters recognize and trust. But beneath its well-known name are two groups that no longer have a common Communist enemy and, therefore, no longer have much in common.

On one side are intellectuals, businessmen and entrepreneurs, who are enthusiastic backers of the government's plan to rebuild the economy by relying on free-market mechanisms and generous foreign assistance.

On the other are workers and union leaders, who say they are unfairly victimized by the changes that have driven down living standards by about 40 percent while coddling holdovers from the Communist regime and creating a Solidarity elite.

Walesa's critics in Warsaw say that another major reason for the split in Solidarity is his small circle of advisers. They say that since last fall, Walesa's most capable advisers and speech writers -- intellectuals such as Michnik and Mazowiecki -- have been busy with their jobs in Warsaw.

The political handlers who work with Walesa in Gdansk include the twin Kaczynski brothers, Lech and Jaroslaw, and Krzystof Pusz. Last fall, in a move that sparked widespread criticism and mass resignations, Walesa appointed Jaroslav Kaczynski as chief editor of the Solidarity Weekly newspaper, a post that had been held by Mazowiecki.

The Kaczynski brothers announced last month that Walesa would be the centerpiece of something called the Democratic Center, a kind of Christian democrat, right-of-center organization that would sponsor Walesa's bid for president in the fall. Little has come of their announcement, and Walesa continues to speak as head of Solidarity.