BANGKOK, Jun 20 (IPS) - Deposed Thai premier Thaksin Shinawatra has been ordered back to Thailand from self-exile to hear formal charges of concealing assets in a family property company or face arrest.

The order, by the Department of Special Investigation (DSI), requires Thaksin and his wife, to be back in Thailand before Jun. 29 or face a possible arrest warrant being issued.

"All must come in person, including Thaksin who cannot use political circumstances as an excuse or authorise any representatives," DSI director-general Sunai Manomai-udom told local media.

The DSI accused Thaksin, a multimillionaire businessman before entering politics, and his wife Pojaman of concealing shares in the property company, SC Asset, a listed firm, violating the Securities and Exchange Act.

The move marks a new twist in efforts to end Thaksin's political influence as well as investigate corruption allegations during his five years in power, beginning with the Sep. 19 coup.

Interim Prime Minister Surayud Chulanont told reporters the government would guarantee Thaksin's safety if he chooses to return and fight the charges against him.

The DSI's call for Thaksin and his wife to return to Thailand comes after the former leader, last Friday, in a pre-recorded 28-minute message, accused the junta and military-appointed government of treating him unfairly.

Addressing a smaller-than-expected crowd of 10,000 supporters, Thaksin accused the junta of undermining the country's reputation and economy and abuse of the law. Thaksin said he would return to Thailand to fight the charges and "protect his dignity."

His comments -- permitted by the interim government and the first to such a large audience in Thailand since his ouster in the coup -- came at the end of a period of setbacks to his chances for a political come back.

On May 30 the Constitutional Tribunal found his eight-year-old political platform, Thai Rak Thai (TRT) Party, guilty of fraud during the 2006 general elections, dissolving the party and banning 111 party executives - including Thaksin - from politics for five years.

A week ago an Assets Examination Committee (AEC), appointed by the junta, froze 21 bank accounts of Thaksin and his family containing up to 52 billion baht (1.6 billion US dollars). Thaksin told the rally the freezing of his assets was a "ploy" by the junta to isolate him politically.

Thaksin was given 60 days, under the law, to appeal the freeze order and prove the funds were earned legally.

The AEC, comprising senior auditors and judges, listed charges of corruption and abuse of power by Thaksin, favouring his business interests and family while in office leading to billions lost in tax revenue.

Thaksin has also been accused of human rights abuses and efforts to extend his power through appointments in the military, police and bureaucracy, as well as harassing the media.

Gen. Sonthi Boonyaratglin, leader of Council for National Security (CNS), told a seminar on Monday that plans to prosecute Thaksin over corruption charges and prevent his return to politics were on target. "Everything is going according to plan and the AEC's work is progressing steadily," Sonthi said.

But former senator Kraisak Choonhavan said the committee's move to freeze Thaksin and family accounts would provoke the former leader.

"He will use whatever money that he has obtained, whether hidden abroad or in other nominee assets, to cause more disruptive movements in Thailand that's for sure, I'm quite certain of that," Kraisak told IPS.

Other analysts, including brokers Phatra Securities, in a commentary had warned prior to last weekend's rallies, that a state of emergency may be declared in Bangkok together with the arrests of key rally leaders.

But instead of the 50,000 attending ahead of Thaksin's address last Friday, just 10,000 were there in part due to the military preventing supporters from travelling into Bangkok.

Also reports said police had warned registered motorbike taxi drivers, a key support base in Bangkok for Thaksin and who had charged at the police lines at recent rallies. Sonthi said he expected the protests would fail to topple the government, with intelligence reports putting the "hardcore" protestors at just 2,000.

Panitan Wattanayagorn, a political scientist at Chulalongkorn University, told IPS that many are watching Sonthi as he is due to retire as army commander on Sep. 30. Panitan says Sonthi was now more outspoken and his next move may be to enter politics.

‘The Nation' newspaper, in a commentary Wednesday, said Thaksin is now likely to alter strategy. "Instead of instigating protests in Bangkok, which have not worked, as they have been blocked by the junta -- and also won little support from the middle-class -- he could order his former MPs (members of parliament) back to their provincial bases to rally against the junta," the commentary said.

By this Thaksin would hope his nominees win this year's elections, set by the interim government to be held by December. If the nominees win, it adds, they would be in a position to grant an amnesty to the 111 banned executives of the TRT.

Thaksin's political support among the poor and working classes,thanks to TRT's populist political policies,is sound and expected to be a source of electoral support if he seeks to return to politics, analysts say. Reports said he may be willing to spend up to 10 billion baht (290 million dollars) in a bid to win back power.

At last Friday's rally many stood by their fallen leader. A 69-year-ld medical practitioner, who called herself ‘Dr. Pat', said there were still those who believed he was not corrupt.

Dr. Pat said she feared for Thaksin's safety if he returns to face the courts. "We would like him to come back but we're not sure about his safety -- about the assassination -- it's maybe or maybe not, right?"

"We still support Thaksin,'' Dr. Pat said. ‘'I think all the people here would like to support Thaksin because for the other party we do not see any result in the past, they just keep talking.''