Warsaw - Union members in Warsaw left Prime Minister Donald Tusk's office on Friday morning after spending two nights in the building, threatening a general strike and saying it was "cowardly" to relocate the office.

Members of "August 80" - a more hard-line group than the Solidarity union - have been occupying Tusk's offices since Wednesday in protest over a bill that would slash early retirement. But they left the building on Friday morning after officials said Tusk's office had been temporarily relocated.

Tusk was in Frankfurt on Wednesday and in Paris on Thursday for meetings, but offered the unionists a meeting with government officials. He said there were "better ways" to hold talks.

The unionists rejected the meeting, and said they wanted to see Tusk directly.

The union members said they were protesting against proposed cuts in the number of people eligible for early retirement, privitizing hospitals and eliminating the Polish shipyard industry.

Tusk was slated to meet on Friday with a commission for socio-economic issues, an organization for dialogue between government and trade union representatives. The commission had discussed early retirement at their last session.

Boguslaw Zietek, head of "August 80," told the Polish Press Agency PAP that if the commission failed to reach an agreement, the union will call a general strike for December 8.

"It's a good date for the whole country to show the Prime Minister that there's no agreement for this type of reform," Zietek told PAP, "that ruins society, is anti-labour and serves only 5 per cent of the richest."

Prosecutors will take up the case, and say the unionists could face up to a year in jail for occupying Tusk's offices.

Former Solidarity leader Lech Walesa had spoken out against the unionists and said they had crossed the line.

Walesa became for many an anti-communist icon when he lead strikes in the shipyards of Gdansk that later helped topple Poland's communist regime in the 1980s.

But Walesa said if he was Prime Minister, he'd "use force" against the unionists if argument didn't work. Conflicts in a democracy had to be resolved with elections and changes in law, he said.

The European Commission has demanded that Poland restructure the Baltic Coast shipyards where Solidarity was launched, or risk losing public aid.

The lower house of parliament approved a bill last week that would reduce the number of people eligible for early retirement from 1.2 million to 250,000. The bill must still be approved by the Senate (dpa)