Thailand is offering its naval airbase on the eastern seaboard as an alternative for airlines after its two Bangkok airports were closed by anti-government protests.
Officials say international airlines can use U-Tapao, a small airport 140km southeast of Bangkok. Thousands of travellers remain stranded in the city.
Anti-government protesters in Thailand blockaded and shut down a second airport on Thursday, after forcing the closure of Suvarnabhumi international airport.
Supporters of the People's Alliance for Democracy began massing at the main entrance to the Don Mueang airport on Wednesday evening. Flights were cancelled at about midnight until 6pm local time on Thursday.
Don Mueang serves domestic flights and was the only airport left serving the capital after protesters swarmed Suvarnabhumi airport on Tuesday night.
Suvarnabhumi airport is a regional hub with about 125,000 passengers passing through it daily. Most airlines have halted services there.
It has been occupied by anti-government protesters since Tuesday.
New Zealand's ambassador in Thailand says most tourists have left Suvarnabhumi airport and are staying at hotels around Bangkok.
About 3000 New Zealanders are thought to be in Thailand. They are being advised warned to avoid all political rallies.
New Zealand ambassador Brook Barrington says embassy personnel have visited the airport, which he says feels more like an airport shut by fog, than protest activity.
PM rejects call for fresh elections
On Wednesday, Thai Prime Minister Somchai Wongsawat rejected a call by army leader General Anupong Paochinda for new elections to end the political deadlock.
Mr Somchai says his government is legitimate and that he will continue to work for the country.
Thailand has been in a state of political stalemate since former Prime Minister Thaksin Shinawatra was ousted in a military coup in 2006.
Fresh elections at the end of 2007 failed to resolve the crisis, when a party made up of former allies of Mr Thaksin returned to power.
General Anupong's call on Wednesday for an election heightened speculation that another military coup could be imminent. But the army chief denied that was his plan, saying the government still had "full authority".
Mr Somchai has said he will not be giving in to anti-government protesters who he says are trying to destroy democracy with mob rule. He says his Cabinet will discuss what action will be taken against them.