Mr Thirapat Sereerangsan, who was minister to the premier's office, insisted the coup against Thaksin was justified, even though his allies have swept back into power after elections in December.

'The military coup made a positive contribution to Thailand, which was not under democratic rule but under a democracy used for the benefit of capitalists,' Mr Therapat told reporters.

The former minister helped organise street protests against Thaksin in 2006, accusing him of using his political office to enrich his multi-billion-dollar business empire.

The protests eventually led to the coup by royalist generals, who opened a slate of corruption investigations against Thaksin. He has been charged in two cases.

'Today I declare myself the eternal enemy of anyone who exploits democracy by interfering in the judicial process, or in independent agencies such as the National Counter Corruption Commission,' he said.

'People who love justice will rise up and our country will plunge into mutiny' unless the cases against Thaksin proceed, he said.

He also warned the new government against granting an amnesty to Thaksin, who was banned from politics for five years by a military-appointed tribunal.

Authorities have also frozen about two billion dollars worth of his assets, pending an outcome of the corruption investigations.

Thaksin has been living in self-imposed exile in Britain since the coup in September 2006. He has denied any wrongdoing and told a court last month that he would return in May to defend himself. -- AFP