(Bloomberg) -- Former Thai prime minister Thaksin Shinawatra, who has lived in self-imposed exile for 15 years, is set to return to the Southeast Asian nation next month, a move likely to add to the political chaos that’s gripped the country since a May general election.

Thaksin, who turned 74 on Wednesday, will arrive in Bangkok on Aug. 10, his youngest daughter Paetongtarn Shinawatra, said in an Instagram post. She is among the three prime ministerial candidates of Thaksin-backed Pheu Thai Party, which is now leading the efforts of a pro-democracy coalition to form a new government and end a near decade-long military-backed rule.

It’s not the first time that Thaksin, a popular but polarizing politician, or his family has announced his plan to return to the country where he was ousted as the premier in a military coup in 2006. As recently as in May when the nation was in the middle of election campaign, he pledged to return before his birthday to raise his seven grandchildren.

But this time it will be different, Paetongtarn said, adding that preparations were underway to welcome him back. The Shinawatra family — an influential political dynasty — was happy and also concerned at the same time about Thaksin’s plan, she said.

The timing of Thaksin’s homecoming coincides with efforts by Pheu Thai to drum up support among pro-royalist political parties in the lower house and the nation’s conservative Senate, which holds the key to the country’s top political office under rules designed after a 2014 coup to entrench establishment influence in Thai politics. 

READ: Pheu Thai to Seek Senate Support While Sticking With Allies  

The eight-party democratic bloc has struggled to take power despite commanding a majority in the 500-member elected lower house. It’s short of the half-way mark in a joint sitting of the bicameral assembly whose current strength is 748.

The conservatives thwarted Pita Limjaroenrat, the coalition’s first prime minister candidate and leader of the progressive Move Forward Party, citing opposition to his reformist platforms that include amendments to the country’s harsh royal insult law.

The delay in government formation has weighed on Thailand’s stocks with foreign investors pulling out more than $3.5 billion this year. While the selling pressure has eased on prospects of a Pheu Thai-led government, many senators have ruled out support for a coalition that includes Pita’s party. 

Pheu Thai has also held talks with conservative parties in recent days, fueling speculation that it may snap the alliance with Move Forward in exchange for support from conservatives to form a government.

READ: Thai Political Gridlock Grows as Pro-Democracy Bloc Wobbles  

Thaksin’s homecoming announcement signals that a deal between Pheu Thai and the conservative establishment is in the works, though doubts remain if the former leader will stick to his plan, said Peter Mumford, Southeast Asia practice head at consultancy Eurasia Group.

“As this is not the first time Thaksin has announced he will be returning to Thailand, the latest comments do not necessarily signal that a Pheu Thai-conservatives deal has been finalized already,” said Mumford.

Parties backed by Thaksin, with his large following among the rural voters, had won the most seats in every national vote between 2001 and 2019, only to be unseated from power by dissolutions or coups.

Corruption Charges

Thaksin has lived overseas since fleeing the country in 2008 to avoid corruption charges, shuttling between Hong Kong, Singapore, Dubai and London. Since leaving Thailand, he had been found guilty in absentia in several graft cases he said were politically motivated, and still faces a combined 10 years in prison in three cases if he returns.

Thaksin said in May that he would enter the justice process upon his return and that he didn’t want an amnesty from jail terms — something previously attempted by a government headed by his sister Yingluck Shinawatra in 2013 before it was toppled in the 2014 coup. 

Thai police is set to take Thaksin into custody when he lands in Bangkok and produce him before the Supreme Court, which may order his detention at Bangkok Remand Prison, Thai-language Matichon newspaper reported, citing police officers. 

Paetongtarn, 36, may have a shot at being nominated for premiership once her party secures backing of enough lawmakers. Pheu Thai’s candidates also include property magnate Srettha Thavisin and former attorney-general Chaikasem Nitisiri.

The party has not announced which of the three will be nominated in the next round, after a vote this week was called off pending a petition by the Office of the Ombudsman to the Constitutional Court on the legality of parliament last week rejecting Pita’s re-nomination.

(Updates with police’s plan for Thaksin’s arrival in 15th paragraph.)

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