Australians currently in Thailand, and even those who need to go there, have been strongly warned to exercise all necessary precautions, following the confirmation of a military coup. Travel insurance companies have expressed the policies of travelling Australians in Thailand may be cancelled because of the development.

Travel insurance InsureandGo has currently denied applications for Australians planning to travel to Thailand, a report by the SMH said.

They "are currently unable to purchase a policy with the company," SMH quoted Julius Paramour, InsureandGo operations manager.

For Australians currently in Thailand, "InsureandGo will take all reasonable measures to assist its customers in Thailand... as per standard practice."

Claims involving martial law and coups are usually not part and parcel of what can be claimed from travel insurance policies. Most state these exclusions in the fine print of their product disclosure statements.

"Claims arising as a result of war, invasion, act of foreign enemy, hostilities (whether war be declared or not), civil war, rebellion, revolution, insurrection or military or usurped power," are explicit exclusions noted in the policies of leading travel insurers CoverMore and Medibank Private, the SMH report noted.

The Insurance Council of Australia said it will give the prerogative to the individual insurers to lay down and decide their own "terms and conditions" to Australians wanting to travel to Thailand.

On Tuesday, Thailand's army declared martial law to maintain and control the deepening political crisis in the country, spurred by the chaos brought by the nation's political rivals that has led to mass demonstrations and the death of some 28 people.

"We advise you to exercise a high degree of caution in Thailand due to the possibility of civil unrest and the threat of terrorist attack. You should pay close attention to your personal security at all times," a statement on the Australian Department of Foreign Affairs and Trade Web site posted on Tuesday said.

Authorities have no idea on the exact number of Australians in Thailand right now, although those registered with DFAT's Smartraveller Web site tallied at 5,000.

"Australians should follow the instructions of local authorities and avoid all demonstrations, protest sites, political events and large-scale public gatherings. Australians travelling to Thailand should visit www.smartraveller.gov.au, familiarise themselves with the travel advice, subscribe to receive regular updates and register their travel plans."