Mr Thaksin was driven from office in a bloodless coup last year

A committee investigating claims of corruption during Mr Thaksin's era said it had ordered accounts worth 52.9bn baht ($1.63bn, �830m) to be frozen.

Mr Thaksin has been under investigation since his ousting in a coup last year.

His lawyer said the new move was politically motivated and that the ex-prime minister would challenge it.

"It is a political decision that is legally baseless," Noppadol Pattama told Reuters news agency. "The aim is to prevent the ex-PM and his wife from running their own normal lives."

Manchester City bid

Mr Thaksin is reported to be involved in a bid to buy English Premier League club Manchester City.

On Monday morning AFP quoted Mr Noppadol as saying that the football club deal, estimated at about �100m ($197m), was progressing well.

"The negotiations are underway, in line with English law. The result is likely to be good, and the negotiations should not take a long time," he was quoted as saying.

However, correspondents say it could be affected by the asset freeze.

The Assets Examination Committee, set up by the country's new military rulers after last year's coup, said it had concluded that Mr Thaksin had "committed wrongdoings".

It issued two orders covering the former prime minister's assets.

Telecoms sale

The first freezes 21 accounts holding money made from the controversial sale in January 2006 of Shin Corp, Mr Thaksin's telecoms giant, to a Singaporean firm, committee spokesman Sak Korsaengruang said.

The sale sparked days of street protests in Bangkok and was a key factor in the political unrest that preceded the military coup.

The second order freezes an unspecified number of accounts Mr Thaksin and his wife hold in Bangkok pending a corruption probe, he said.

The couple had 60 days to appeal against the decision, he said.

Thailand's military ousted Mr Thaksin in September 2006, accusing him of corruption and abuse of power.

He was out of the country at the time and now lives in exile in London.