Thailand's Constitutional Court is set to decide whether to remove Prime Minister Yingluck Shinawatra from office on abuse of power charges, a ruling that threatens to plunge the kingdom further into turmoil.

Wednesday's legal procedure comes as Shinawatra stands accused in the country's highest court of abusing her authority by transferring a senior civil servant in 2011 to another position, allegedly for the benefit of herself or her Pheu Thai Party.

The court could also rule her Cabinet liable as well, and force all ministers out of office, leaving a power vacuum that the government's opponents hope to fill with their own loyalists.

"I would like to deny all allegations I am accused of," Yingluck testified on Tuesday. "As the prime minister, I am entitled to carry out responsibilities I have toward the people ... and for the utmost benefit of the general public."

Sacking Yingluck and her cabinet could send the nation into uncharted territory, leaving it without a premier, cabinet and lower house - which was dissolved to hold elections in February that were later annulled, AFP news agency reported.

Yingluck appears trapped by legal moves against her premiership after six months of street protests that have left 25 people dead and hundreds wounded in gun and grenade attacks.

The court, notoriously unsympathetic to her government, is widely expected to rule against Yingluck, reported the Associated Press news agency.

Fears of clashes

Anti-government protesters have taken to the streets in the country's capital city of Bangkok.

"Prime Minister Yingluck is (the protesters') obstacle in overthrowing democracy," Jatuporn Prompan, chairman of Yingluck's "Red Shirt" supporters said on Tuesday. "I expect the verdict will not be good for the government.... I heard they want to sack the entire cabinet.".

His group has vowed to come out on the streets if Yingluck is toppled, kindling fears of clashes between rival political sides.

The Red Shirts say they are unarmed, but have held several training camps in their rural northeastern heartlands for guards to protect their future rallies.

The Constitutional Court oversees cases of violations of Thailand's charter, which was rewritten after the removal of Yingluck's brother, billionaire former premier Thaksin Shinawatra, by an army coup in 2006. Thaksin lives overseas to avoid jail for corruption convictions.

Critics accuse it of driving through Yingluck's case and allege previous rulings show that it is politically biased against the Shinawatras.

In 2008, the court forced two Thaksin-linked prime ministers from office. It also annulled the February election called by Yingluck to shore up her flagging administration, citing widespread disruption by opposition protesters.

Yingluck has also been charged by anti-graft officials with neglect of duty in connection with a costly rice subsidy scheme that critics say fomented rampant corruption.

An unfavourable ruling by that body could also lead to her impeachment and a five-year ban from politics.

Source: Associated Press, AFP