The Dec 12-17 Asean meeting, which was initially scheduled to take place in the capital Bangkok, was shifted last month to the northern city of Chiang Mai.

Anti-government protesters have besieged the prime minister's office compound in Bangkok since August and last week moved thousands of protesters to Bangkok's two main airports, shutting down air transport to the Thai capital.

'The Cabinet agreed to cancel the Asean meeting until March because of the political turbulence in Thailand,' said government spokesman Nattawut Sai-Kua. As the current chair of Asean, Thailand was to host the grouping's annual summit.

The government's announcement came shortly after the Constitutional Court in Bangkok dissolved the three biggest parties in the ruling coalition and banned Prime Minister Somchai Wongsawat from politics for five years.

The ruling sinks Mr Somchai's coalition government, made up of six parties, and raises hopes that protesters seeking the government's ouster will end their siege of the country's two main airports.

Several Asean members publicly raised concerns earlier in the week that Thailand's ongoing political turmoil could force the meeting's cancellation.

Thousands of members of the protest alliance have taken over the main Suvarnabhumi international airport and the domestic Don Muang airport for about a week, cutting off all commercial traffic to the capital and stranding more than 300,000 foreign travelers here. -- AP