"Normally, politics and business are not related," he said, adding that both countries should negotiate soon to settle their differences. He also said this should not have any impact on the overall economy.

An FTI survey revealed that no federation members have direct business with Singaporean investors, and that no Thai businessmen have invested in Singapore, he added.

Deputy Prime Minister and Finance Minister MR Pridiyathorn Devakula also insisted that the Kingdom's abolition of high-level diplomatic cooperation with Singapore would not hurt the overall economic picture.

He said the government would ensure fair treatment for Singaporean investors who are doing business in Thailand.

"Diplomatic ties are not related to the overall economic picture. Our treatment of Singaporean investors will remain impartial," he told reporters.

Pridiyathorn expressed pleasure at Thailand's improved ranking in the Heritage Foundation's economic freedom index, saying that boosting freedom is a government obligation. In Asia, Thailand is now ranked ninth, up from 12th the previous year.

He admitted that Prime Minister Surayud Chulanont had not consulted him before initiating retaliation against Singapore's generosity towards ousted prime minister Thaksin Shinawatra.

"Whatever he does, we have to follow. You get it?" he said.