BANGKOK (AFP) –
Cambodian officials allowed Thai diplomats Tuesday to make their first visit to a Thai national held on charges of spying on fugitive former premier Thaksin Shinawatra, the Thai premier said.

Siwarak Chothipong, 31, an employee at the Cambodia Air Traffic Service, was arrested Thursday on charges of supplying details of Thaksin's flight schedule to his country's embassy when the Thai tycoon visited Phnom Penh last week.

His arrest deepened a diplomatic crisis between the neighbouring countries over Cambodia's appointment of Thaksin as an economic adviser and its refusal to extradite the ousted prime minister to Bangkok.

Thai Prime Minister Abhisit Vejjajiva welcomed the Cambodian move but said the government was still mulling further measures after withdrawing its ambassador earlier this month, a move that Phnom Penh reciprocated.

"I think it's good that Cambodia has allowed the visit, we think that's the right attitude. But the foreign ministry is still compiling measures," Abhisit told reporters in Bangkok.

Chavanond Intarakomalyasut, secretary to the Thai foreign minister, said the charge d'affaires at the Thai embassy and four embassy officials had visited Siwarak earlier Tuesday.

"He told diplomats that he was well treated. We are asking him about the case details, the charges, how we can defend him and who should be appointed as a lawyer," Chavanond said.

Siwarak was also allowed to talk to his mother in Thailand on the telephone for the first time since he was arrested, he added.

Cambodia expelled the first secretary of Thailand's embassy in Phnom Penh last Thursday after alleging that Siwarak had passed information to the diplomat. Thailand reciprocated hours later.

Thaksin was toppled in a coup in 2006 and is living abroad to avoid a two-year jail term for corruption, but he has been stirring up protests in his homeland against the current Thai government for the past year.

Angered by his presence in Cambodia, Thailand last week put all talks and cooperation programmes with Cambodia on hold and tore up an oil and gas exploration deal signed during Thaksin's time in power.

Tensions were already high between the two countries following a series of deadly military clashes over disputed territory near the 11th century Preah Vihear temple on their shared border.