He cited information provided by the army's Internal Security Operations Command (ISOC), which has played a lead role in detaining and expelling Rohingya. 'All those who arrived illegally have been escorted out of Thailand,' Mr Thani said.

Recent investigations by the South China Morning Post have revealed that nearly 1,000 Rohingya were towed out to sea and abandoned, in boats with no engines or sails, by the Thai army last month. Hundreds died as a result.

The latest expulsions were carried out humanely, said Mr Thani, citing ISOC information. 'Their vessels have been repaired with engines, and they were provided with necessary food, water and medicines.'

Asked if the refugees had been sent back to Myanmar or Bangladesh, Mr Thani declined to speculate. 'We don't know where they came from. We escorted them back into international waters.'

The United Nations High Commission for Refugees has expressed serious concerns over the reports about Thai authorities' treatment of the Rohingya.

On Tuesday it asked for access to 46 boatpeople detained by the Thai military four days earlier, and to 80 it believed were being held on Koh Sai Daeng. The Post visited the island on Tuesday and found it newly deserted.

Kitty McKinsey, a UNHCR spokeswoman in Bangkok, said yesterday that the Thai government had still made no formal response to its request for access to any Rohingya in Thai custody. She declined to comment on the latest Foreign Ministry statements.

However, Prime Minister Abhisit Vejjajiva said yesterday he was prepared to offer the UNHCR access to any Rohingya detained in future by Thai authorities, according to reports on the websites of the Bangkok Post and The Nation newspapers. He reportedly said the UN agency could file requests with the foreign ministry. It was not possible to verify these reports last night.

Mr Abhisit had earlier promised a full investigation into the treatment of Rohingya. But he has also said that Thailand is being flooded by illegal immigrants, and that those detained should be sent back. The Thai army confirmed last week that it had been funding a programme under which villagers were trained to round up Rohingya before they were sent back out to sea. The army has denied mistreating the Rohingya and categorised the process as helping the boatpeople on their way.

Mr Thani said any boatpeople who arrived in Thailand would be subjected to the same push-back policy under the auspices of both the military and immigration officials.

He said the government was awaiting a final ISOC report on the treatment of the Rohingya this week, which it would compare to the recent media reports.

On Friday, foreign ministry officials met envoys from India, Indonesia, Bangladesh, Malaysia and Myanmar to discuss the exodus of refugees.

Not welcome

The estimated number of refugees the Thai army expelled last month: 1,000