PRAGUE: Opponents of the Czech Republic's president have gained sufficient support to attempt to press high treason charges against him over his controversial amnesty.

To mark the country's 20th anniversary of independence on Jan. 1, Vaclav Klaus used a traditional tool of Czech presidents and ordered the release of more than 6,000 inmates serving short prison terms.

But what really infuriated many Czechs was that the decree also halted court proceedings in several high-profile fraud cases and financial scams on the grounds he wanted to stop "endless criminal proceedings."

The office of the Senate, Parliament's upper house, said Wednesday that 28 lawmakers - one more than needed - have requested the issue to be debated. It said Speaker Milan Stech now has to set a date for an extraordinary session, possibly Monday.

Only the Senate has the power to file treason charges at the Constitutional Court. A majority of the present lawmakers in the 81-seat house, which is controlled by the left-wing opposition, has to approve that to happen.

Klaus doesn't have much to worry about because the major punishment he faces would be loss of the presidential job: his second and final term in office ends March 7.

But the amnesty has touched a raw nerve in a nation that has become increasingly angered by widespread corruption. About 73,000 Czechs have signed a petition, backing the charges while Klaus' portrait has been torn down in anger in schools and offices across the country.

A group of 30 senators has already challenged Klaus' decree at the Constitutional Court.

But the conservative president has previously said he doesn't regret the amnesty and "would do it again in the absolutely same way."

During his visit to Slovakia on Wednesday, Klaus called the move by the opposition lawmakers "political games."

Prime Minister Petr Necas, who is chairman of the Civic Democratic Party that Klaus established, said he was feeling ashamed that the lawmakers want to sue the president.

"Shame on them," Necas said.