The Thai government on Tuesday suggested its people postpone their trips to swine flu-hit countries if it is not necessary.

The Thai Public Health Ministry's latest suggestion came out after the World Health Organization (WHO) Monday raised its pandemic alert level from Phase 3 to Phase 4, warning of a significant increase in the risk of a pandemic.

"The Public Health Ministry has not yet prohibited Thai from traveling to the swine flu-hit countries. However, if it is not necessary to travel to those affected countries, they should postpone their trips," said Witthaya Kaewparadai, minister of Public Health said in a statement released on Tuesday.

The Thai people should delay their trips to the swine flu-hit countries until the swine flu outbreaks stop, Witthaya said.

However, if they have to travel to those swine flu-hit countries, they should avoid entering into crowded areas and follow all of suggestions by those swine flu-hit countries strictly, the minister said.

Also, they should wash their hands often as they are staying in those swine flu-hit countries, Witthaya said.

For foreign tourists arriving at Thailand's international airports, including Suvarnabhumi Airport in Bangkok, the airport authorities currently have focused on those who come from the swine flu-hit countries, Witthaya said.

If anyone is detected by infrared thermo scanners of having a high body temperature, the airport authorities would question their history and will require an additional physical check, Witthaya said, adding if confirmed of having the swine flu, he or she will be sent to a hospital, which has already been prepared.

Currently, Thailand has a stockpile of Tamiflu anti-virals enough for at least 300,000 patients, said Witthaya.

Thailand's government from Monday has ordered installation of the thermal scanners at the country's three international airports, including of Suvarnabhumi International Airport in the capital Bangkok as a preventive measure against the potential spread of swine flu.

The infra-red cameras, which are used to detect unusual body heat in a bid to prevent the spread of swine flu, were also installed at Thailand's international airports during the outbreaks of severe acute respiratory syndrome or SARS in 2003.