Suvarnabhumi international airport in Thailand, one month before the protests.

flickr.com/jason_weemin

Foreign Minister Stephen Smith has expressed frustration with Thailand's failure to quickly evacuate Australians stranded in Bangkok because of the ongoing anti-government airport blockade.

Hundreds of Australians remain stuck in Bangkok after protesters seized control of the Suvarnabhumi international airport last Tuesday and the smaller Don Muang domestic airport last Wednesday.

Australian authorities have been negotiating with their Thai counterparts to put on more flights from Utapao, about 150km from Bangkok, and the tourist resort of Phuket, about 900km away.

But some of the few Australians who managed to get on planes out of a military base at Utapao at the weekend have complained that the flights were returning to Australia only half full.

Mr Smith said the main problem had been "logistical difficulties" in people being able to get access to the airports.

"We have been becoming very frustrated with the Thai authorities, particularly Thai airline authorities and tourism authorities," he told AAP.

"We are working with Qantas to get as many stranded Australians back to Australia as soon we can.

"But the two main airports in Bangkok are still closed, so we are looking to use a military airport 150km away and one in Phuket."

Mr Smith said once extra flights were organised to take Australians home, officials would organise buses to take the stranded tourists on the long journey to either Phuket or Utapao.

In the meantime, he hoped the political turmoil gripping Bangkok would be resolved peacefully.

"We are urging a peaceful and political resolution to it and the last thing we want to see is a military resolution," he said.