Pakistan government has warned clerics heading seminaries and mosques that they will be put behind bars if they take part in "anti-government" activities or speak against President Pervez Musharraf, who has been critical of the fundamentalists in his country.

Top police officials held three meetings with local clerics recently where they were told to stop participating in protest gatherings and giving speeches against the president and government policies, at least till the next general elections, officials were quoted as saying by Daily Times.

The clerics were told that if they did not stop, cases would be registered against them and they would be imprisoned.

The clerics, who enjoyed unfettered influence under army regimes and forged close alliance with the military in nursing the militant groups to carry out jihad for various causes, have been restive since Musharraf joined the United States' war against terror in the 9/11 aftermath and altered several policies.

This lead to friction between Islamist alliance Muttahida Majlis-e-Amal and Musharraf, with the government threatening to crack down on the clerics if they do not fall in line.

After warning clerics in the national capital, the government intends to spread the message across the country.

The security officials told the clerics that they had recordings of their Friday sermons and anti-government speeches at protest gatherings, the newspaper said.

The clerics were also told that mosques built on encroached land would be demolished.