Exiled former Thai premier Thaksin Shinawatra denounced his opponents Saturday in a telephone address to 90,000 loyal supporters packed into a Bangkok sports stadium.

Speaking from an undisclosed location Thaksin thanked the crowd but told them he could not return to the kingdom from exile in Britain without a royal pardon after he was sentenced to two years in prison on corruption charges last month.

"I cannot return home because I was sentenced to two years' imprisonment," he said, adding that the case against him would be valid for another decade.

Thaksin went on to verbally attack the generals who overthrew him in a September 2006 military coup, to wild cheers from the crowd.

"They have abused the legal process to get rid of me. I was overwhelmingly elected prime minister twice yet I was overthrown in a military coup, and survived an attempted assassination," he said.

"My family and I have been attacked, our assets have been forfeited and I have been sentenced to jail, but my problems cannot compare to those facing our country," he said.

"Nobody can bring me back to Thailand except royal mercy or the power of the people," he added. His address was not carried by any Thai television or radio channels.

Thaksin fled to Britain in early August following his wife's conviction for tax evasion.

It was his first address to supporters since leaving the kingdom and being sentenced in absentia on October 21 to two years in jail for violating corruption laws. Several other corruption cases are outstanding against him.

About 90,000 of his fans, clad in red shirts signalling their pro-government stance, gathered at Rajamangala sports stadium in Bangkok's eastern outskirts, raising fears of clashes with rival protesters.