BANGKOK, THAILAND - THE repatriation of thousands of foreign passengers following protests which have paralysed Bangkok's airports could take up to a month, the deputy premier said on Saturday.

The effects on Thailand's tourism industry are set to be 'mammoth', with up to one million Thais facing losing their jobs and the number of visitors from abroad falling by half next year, Olarn Chaiprawat said.

Around 30,000 passengers a day are missing flights because of the closures, and with travellers currently being evacuated from a Vietnam War-era navy base in eastern Thailand, progress has been slow.

Bangkok's Suvarnabhumi international airport closed on Tuesday after protesters stormed the terminal and authorities shut Don Mueang domestic airport on Thursday after a similar blockade.

Mr Olarn said up to 50,000 Thais were stuck abroad because of the occupation, which police have shown no signs of wanting to end amid fears of bloody clashes with protesters.

The operation to repatriate foreigners and Thais would cost at least one billion baht (S$42 million dollars), he said.

Special check-in desks are being set up at six hotels in the capital but are not yet open, Tourism and Sport Minister Weerasak Kowsurat said.

'We expect it will take one to two days to make the operation of city terminals ready to start,' he said.

Mr Olarn said the protests were devastating for Southeast Asia's second biggest economy.

'The damage is mammoth. The government needs to seek measures to relieve severe problems for the medium and long terms,' Mr Olarn said.

'The number of foreign tourists next year to Thailand is expected to drop at least by half of this year when around 13.5 million tourists visited Thailand,' he said.

'That will affect the tourism industry and other tourism-related businesses next year and around one million Thai workers are estimated to become jobless,' he added.