Bangkok - Foreign Ministry says remarks unacceptable.

A fresh onslaught of insults by Cambodian Prime Minister Hun Sen directed at Abhisit Vejjajiva is widening the diplomatic gulf between the two countries.

Thailand and Cambodia had been struggling to find ways to mend fences after a series of spats but Hun Sen yesterday appeared to want nothing of the kind.

He scrapped a visit to Ta Muan Thom, an ancient border temple in Phnom Dong Rak district of Surin.

Diplomatic tensions did not ease despite Hun Sen not turning up at the temple and he fired a broadside at Prime Minister Abhisit on a Cambodian website.

The Thai embassy in Phnom Penh alerted the Thai government to the remarks on the website and the Foreign Ministry was quick to counter the Cambodian leader.

"I have to apologise to the Cambodian people that up until today all Thai people and the government have wanted to resume relationships with Cambodia in all fields, including economic, social and investment cooperation," said Chavanond Intarakomalyasut, assistant to the foreign minister.

"But criticising the Thai premier so badly damages Thailand's dignity and that will make it even more difficult to normalise ties.

"The harsh and rude words should not have come from a prime minister of any country. We cannot accept it.

"It is impossible for any country to resume [good] relations without being respectful of each other first."

Thailand will now press for sovereignty over disputed areas along the Thai-Cambodian border, Mr Chavanond said.

"We have never invaded any place which is not ours. We have the evidence to confirm that the area, including Wat Kaew [Sikha Khiri Sawara] or other areas in the 4.6 sq km [of disputed territory] are under Thai sovereignty."

Tension along the border escalated after Hun Sen concluded his weekend tour of the area yesterday. His itinerary included the Preah Vihear temple.

A military standoff continued yesterday morning around the Ta Muan Thom temple as the army tripled its troop presence to about 1,500 to offset Cambodian troops beefing up security during Hun Sen's visit to the opening ceremony of a military office at Ban O-rumchong, six kilometres inside Cambodia.

"We regard Cambodia's troop increase for Mr Hun Sen as very unusual," said Col Thanet Wongcha-um, chief of staff of the Suranaree Task Force.-- Courtesy of Bangkok Post