Pojaman Shinawatra landed at Bangkok's international airport on Friday night, nearly four months after she fled into exile to avoid graft charges.

'She comes home to visit her mother, who is ill and will have surgery,' Mr Pongthep Thepkanchana, a spokesman for the former couple, told Reuters.

Despite several arrest warrants, police did not detain Pojaman because her appeal against a three-year jail sentence for tax evasion was ongoing, police said.

Mr Pongthep denied local media reports that Pojaman's return was aimed to work out issues in Puea Thai, a new party floated by Thaksin supporters after the ruling People Power Party was disbanded in a court verdict last week.

Pojaman's return from exile is the latest twist in Thailand's three-year-old political crisis, which has pitted Bangkok's royal and military elite against Thaksin, ousted in a 2006 coup, and his allies in the current government.

In the latest escalation, protests by the anti- government People's Alliance for Democracy (PAD) shut down Suvarnabhumi International Airport for a week.

Thaksin remains in exile, his whereabouts unknown.

Reuters