An embattled Prime Minister Abhisit Vejjajiva came under mounting pressure yesterday as the powerful People's Alliance for Democracy continued to press for him to remove the national police chief while the opposition threatened to seek his impeachment.

PAD spokesman Panthep Pua-pongpan said the PM had the power to prevent police chief General Patcharawat Wongsuwan from wielding influence by citing irregularities in the Bt18-million public-relation fund or the October 7 incident to transfer Patcharwat to an inactive post.

"The PM must realise that the government's stability depends on the people's support not three or four people who try to wield influence over him,'' he said.

PAD leader Sondhi Limthongkul warned the ruling Democrats they could be in for political trouble if the prime minister "remains idle" regarding the post of national police chief.

Panthep also urged the PM to make a bold and decisive decision as to who would replace Patcharawat as caretaker national police chief. He said if the PM did not intervene and let Police General Priewpan Damapong, who is most senior, take the top post the Sondhi shooting case would be even more entangled because Priewpan was part of ex-premier Thaksin Shinawatra's family.

Priewpan is the brother of Khunying Pojaman Damapong, Thaksin's former wife.

Patcharawat countered Prime Minister Abhisit Vejjajiva's public announcement that the national police chief had taken 30 days leave by saying he would return from his official overseas trip and come back to work on Monday.

He said the national police chief was fighting back because he did not want to allow any interference in the annual police reshuffle.

Abhisit has been trying to remove stumbling blocks faced by police in the investigation into the assassination attempt on Sondhi by proposing that Patcharawat, who is believed to have stood in the way of police investigation, take leave if he did not want to be transferred.

Panthep said there had been a behind-the-scenes deal before Abhisit announced that Patcharawat would take a long leave and the national police chief fought back by countering Abhisit's statement.

Abhisit appeared moody when reporters pressed him to account for the conflicting stories, insisted that he had talked to all top officials in charge of security including Patcharat, Defence Ministry Prawit Wongsuwan and Deputy Prime Minister Suthep Thaugsuban before Friday and there had not been any problem.

"Everything is all right. Only some people with something to lose are trying to blow up the affair out of proportion, but that is normal,'' he said.

Asked to comment on reports about political interference in the police reshuffle, Abhisit refused to answer and walked away.

The premier said he had no conflict with the top police officer and believed that some groups wanted to manipulate the issue for their own political gain.

Abhisit declined to say who would be appointed acting chief while Patcharawat was absent.

Meanwhile, Pheu Thai Party spokesman Prompong Nopparit said the opposition party was planning to seek the impeachment of Abhisit for interfering in the annual police reshuffle. He said the PM might have violated the Constitution by suspending the reshuffle. "It is possible that the delay in the reshuffle is because politicians want to be in control of the police when the next general election is held,'' he said.

He said the party would gather the signatures of one-fourth of MPs to submit to Senate Speaker Prasopsuk Boondet next week to launch impeachment proceeding against the PM.

The prime minister said yesterday that he was not concerned by the impeachment plan, the Thai News Agency reported.

Stressing that he had violated neither the law nor the Constitution, Abhisit said he had done nothing wrong, despite charges to the contrary from Pheu Thai members.