They threatened to boycott the island-state's products and services and accused it of attempting to take over Thai assets.

The leaders of the group were Supapol Iammethawi, Chaiwat Sinsuwong, Somsak Kosaisuk and Ritrong Likhitprasert.

The protesters marched from Thung Srimuang through Udon Thani city using loudspeakers. Some carried placards with Thai and English messages such as "This land not for rent" and "Singapore get out".

They called on Udon Thani people to join the street demonstration and gathered at Wing 23, which Singapore rents as an airbase and for military training.

Demonstrators took turns to verbally attack Udon Thani Governor Charuek Parinyapol and others who support the lease.

Assembly secretary-general Supapol read an open letter to Prime Minister Surayud Chulanont urging him to review the lease, which dates from 2003.

Protesters handed a letter to Wing 23 commander Surasak Thungthong calling on Singapore to scrap the lease. They also burned effigies of deposed prime minister Thaksin Shinawatra and Singaporean premier Lee Hsien Loong.

The letter stated that the Thai people would unite to condemn and react against Singapore's government and all bad Singaporean businessmen. They would boycott Singaporean products and services, and inform Singaporean people about the mistake that its government and Temasek Holdings had committed.

The group vowed to bring back Thai assets and launch a public campaign to protect Thai natural resources against Singaporean attempts to take them over.

Another open letter to Surayud stated that the government must take a bold and decisive step to review all contracts made with Singapore and take immediate steps to correct the illegal concession signed with Temasek.

Protesters also asked the government to review the country's military relationship with Singapore to ensure that Thailand was not dragged by Singapore and the United States into confrontation with Muslim communities.

Surayud responded to the protest by saying that the government had not discussed the matter and that as for policies towards neighbouring countries, the government would ensure that bilateral relations were not affected, especially with regard to security.

Meanwhile, Singapore newspaper The Straits Times reported that Thailand's push to take over the satellite business controlled by Shin Corp could speed up an overhaul of its diverse assets.

Bankers close to Shin Corp say that an asset-disposal plan will be capped with a change of name. "Shin needs a rebranding, and a change of name will help shed the baggage the group is carrying," said a financial executive close to Temasek's Thai partners.

The Nation

Udon Thani