BANGKOK - Thailand said Tuesday that it was looking into requesting the extradition of the kingdom's fugitive former leader after he was invited to give evidence to a US government human rights panel.

Thaksin Shinawatra, who was ousted by a 2006 military coup and lives abroad to avoid a jail term for corruption, is set to speak to the US committee on topics including deadly "Red Shirt" anti-government protests in Bangkok.

The former billionaire telecom tycoon's invitation to Washington comes after the protracted legal battle for the extradition from Thailand of alleged Russian arms dealer Viktor Bout, who was eventually sent to America last month.

Thai Prime Minister Abhisit Vejjajiva has rejected suggestions that there was a deal to swap Thaksin for Bout.

Thai government spokesman Panitan Wattanayagorn said authorities in Bangkok were legally obliged to seek extradition.

"Of course they have to act on it, they are just looking and evaluating what they have to do. This is a very normal procedure," he said.

"It is expected that in normal circumstances countries will honour the (extradition) treaty, but they may have their own procedures and their own requirements."

He said it was not certain that Thaksin would make the US trip.

Neil Simon, spokesman for the Helsinki Commission, an official US watchdog overseeing human rights and other issues, confirmed late Monday that the event was planned for December 16.

In a letter to Thaksin, the panel said the "recent crackdown on political protesters" was of "particular interest".

The former prime minister - still a hugely divisive figure at home - was invited to give his "perspective on the human rights situation in Thailand, including freedom of the press and freedom of expression".

He will also be asked to speak on the Thai government's efforts to quell a separatist insurgency in the south of the country, which according to activists has claimed over 4,400 lives since it began in 2004.

Thaksin drew wide support from Thailand's rural poor when he was in office and is still held in high regard by many Red Shirts, who accuse the current government of being elitist and undemocratic.

The Reds' rally demanding immediate elections overwhelmed parts of Bangkok for two months before a military crackdown brought the demonstration to a bloody end in May.

More than 90 people were left dead and nearly 1,900 injured in unrest during the protests and many of those killed were civilians.

"I welcome the fact that the US authorities have recognised that the horrific human rights atrocities that occurred in April and May this year are to be fully and independently investigated," Thaksin said in a statement responding to the invitation.

Thai government spokesman Panitan said authorities were considering whether to send a representative to testify at the hearing.

Thaksin is wanted by the Thai government for abuse of power during his time as leader.

Thai courts have also issued a series of arrest warrants on charges including terrorism - an accusation linked to the violent street rallies. The authorities have accused him of bankrolling the protests and inciting unrest.

Thaksin, a former owner of English football club Manchester City, has said the terrorism charges against him are "politically motivated".