(CNN) — Thailand’s parliament on Tuesday voted for real estate tycoon Srettha Thavisin to be the country’s next prime minister, bringing an end to three months of political deadlock.

Srettha, 60, was the sole candidate put forward by the populist Pheu Thai Party and received 482 votes out of a possible 747 in Thailand’s bicameral parliament.

His election comes the same day that Pheu Thai founder and divisive former prime minister Thaksin Shinawatra returned to the country after more than 15 years in self-imposed exile.

Thavisin - who still needs to be endorsed by King Maha Vajirilongkorn before he can officially take office - later vowed to work on improving the lives of Thais across the country.

“I feel greatly honored to be elected as the 30th prime minister of Thailand. I would like to thank every Thai, coalition parties, honorable members of the House of Representatives, every senator who joined the vote today. I will try my best in doing my duties tirelessly to elevate Thais’ lives,” Thavisin said.

A political newbie with a track record in business, Srettha joined Pheu Thai in 2022 before being named one of the party’s three prime ministerial candidates ahead of the election in May.

That poll was won by a popular progressive party, Move Forward, which had proposed radical reforms to capitalize on years of rising anger with how Thailand is governed. However, its efforts to form a government were later stymied by the kingdom’s political elites.

Pheu Thai came second but led efforts to form a new alliance after parliament blocked Move Forward’s leader from becoming prime minister over the party’s pledge to amend Thailand’s strict royal defamation laws, known as Article 112.

In a bid to secure the needed votes, Pheu Thai struck a deal with its former military rivals and in doing so reneged on a promise that it would not work with pro-military parties.

Pheu Thai also campaigned on keeping the military out of politics, but under the new alliance the military-backed Palang Pracharath and United Thai Nation Party will be awarded ministerial roles.

Both those parties are affiliated with coup leader and outgoing Prime Minister Prayut Chan-o-Cha, and linked to the military junta that toppled Pheu Thai’s democratically elected government, led by Thaksin’s sister Yingluck Shinawatra, nearly a decade ago.

The move also subverts the will of millions of Thais who voted for progressive parties in the May election, delivering a powerful rebuke to the country’s military-backed establishment that has ruled Thailand since the 2014 coup.

With Move Forward now in the opposition, the formation of the new government is likely to add fuel to the fire of the progressive movement’s young support base with the potential for mass street protests.

A survey by the National Institute of Development Administration found about 64% of 1,310 respondents disagreed or totally disagreed with the idea of the Pheu Thai party forming a “government with military-backed rivals,” according to Reuters.

The return of Thaksin, a deeply divisive figure who was ousted in a 2006 military coup, now adds a further layer of uncertainty into this febrile political atmosphere.

Despite his physical absence from the country, Thaksin has retained an outsized influence on Thai politics.

Until this year, political parties allied to Thaksin had won the most seats in every election since 2001, but have struggled to hold on to power due to the military exerting its influence, whether through coups or other means.

Speaking to CNN before the May election, Srettha said he is not Thaksin’s man and was keen to focus on fixing Thailand’s income inequality, promote LGBTQ+ rights including same-sex marriage, root out corruption and put the country back on the world stage.

“I want to be a prime minister who can make the difference,” Srettha told CNN. “We really need to be boosting foreign activities. We need to go out and talk to the world. We need to sell Thailand. What are the advantages of investing in Thailand? What do we have to offer the world?”

He also vowed to fix Thailand’s economy. During campaigning, Pheu Thai pledged to give 10,000 baht (about $300) in a digital wallet to every citizen over the age of 16.

“Thailand has been in a bad economic situation for the last five to eight years. We are kind of in a coma. You need a big economic stimulus policy just to get them back on their feet and start being economic producing members of society again,” Srettha said.

But with an 11-member coalition that includes bitter military rivals, it is unclear whether Pheu Thai can govern effectively.

Srettha, who is not a member of parliament, was educated in the United Kingdom and the United States and received his masters in finance from Claremont Graduate School. He worked as an executive for Procter & Gamble in Thailand and later founded real estate company Sansiri with his brother.