PHNOM PENH, Cambodia (AP) - Thailand's ousted Prime Minister Thaksin Shinawatra, whose political battle against his successors has left his country bitterly divided, received a warm welcome Tuesday in neighboring Cambodia, which shares his disdain for the current government in Bangkok.

Thaksin, a globe-trotting fugitive from Thai justice whose sniping at his homeland has kept his countrymen on edge, has now helped stir up a sharp diplomatic clash between the neighboring nations.

The toppled leader is scheduled to deliver a lecture Thursday to more than 300 economists while in Phnom Penh. Last week he was appointed an adviser to the Cambodian government on economic affairs, sparking cries that he was selling out his own country.

He ignited further controversy Monday with an interview in which he made remarks that his critics construed as being insulting to Thailand's monarchy.

Thaksin went into self-imposed exile last year ahead of a court's judgment that found him guilty of violating a conflict of interest law and sentenced him to two years in jail. He served as prime minister from 2001 to 2006, when he was ousted by a military coup after being accused of corruption and showing disrespect to the monarchy.

Thaksin's supporters and opponents have repeatedly taken to the streets since then to spar over who has the right to rule the country, sometimes sparking violence.

The People's Alliance for Democracy, the militant anti-Thaksin group whose 2006 protests helped bring him down and sought to bury his political legacy, announced Tuesday that it would hold a new demonstration against the former leader Sunday over his interview and Cambodian links.

Current Thai Prime Minister Abhisit Vejjajiva, another virulent Thaksin foe, meanwhile said he would seek Thaksin's extradition to serve the jail term and announced that his Cabinet had approved ending talks with Phnom Penh on overlapping offshore territorial claims.

Thaksin flew into the Cambodian capital's military airport aboard a private plane with a party of less than 10 people and was driven into Phnom Penh under very tight security provided by bodyguards of Cambodian Prime Minister Hun Sen.

Cambodian state television later showed the two men meeting at a house prepared for Thaksin by Hun Sen's government. It described the affair as a family meeting, and quoted Hun Sen describing the Thaksin as a close and "eternal" friend. TV footage showed the two men smiling and enthusiastically hugging each other.

Thaksin was quoted as thanking Hun Sen for being faithful to him. Hun Sen has said he has offered Thaksin a place to stay in Cambodia and made him an adviser because of their friendship.

However, the political implications of two opponents of the government in Bangkok joining hands has overshadowed that claim.

Thaksin's surprising appointment soured already poor relations between the two neighbors, which have had small but sometimes deadly skirmishes over their land border in the past year.

Thailand responded to the appointment by withdrawing its ambassador from Phnom Penh, and Cambodia retaliated in kind.

Abhisit said that if Cambodia did not extradite Thaksin, Thailand "will be ready with the proper response." He did not elaborate. Hun Sen has said Cambodia will not extradite Thaksin.

Abhisit's Cabinet on Tuesday approved terminating a memorandum of understanding with Phnom Penh on disputed maritime territory that contains large oil and gas deposits. The cancellation must still be approved by Parliament.

Thaksin is living in exile, mostly in Dubai, to avoid the prison sentence.

He remains at the center of a political fight between his supporters and those of the current government that comes as Thailand considers what may happen when the reign of 81-year old King Bhumibol Adulyadej, the country's constitutional monarch for 63 years, eventually comes to an end.

The king has been in the hospital for almost two months with a lung ailment.

In an interview published Monday on the Web site of the Times of London, Thaksin spoke glowingly of the prospects for Crown Prince Vajiralongkorn once he succeeds his father. But he criticized the king's close advisers for interfering in politics.

Open discussion of the succession issue is delicate, in part because of strict laws that prohibit insulting the king and his family and make such criticism punishable by up to 15 years in prison.

Thai Foreign Minister Kasit Piromya, who was an anti-Thaksin activist before joining the government, said to reporters that Thaksin's interview was offensive to the monarchy, and questioned his motive for making them. Other officials made similar criticisms.