A populist Thai party linked to former prime minister Thaksin Shinawatra has won a vote in parliament to lead the country, hours after the divisive former leader returned from years of self-imposed exile and began an eight-year prison sentence.

Real estate tycoon Srettha Thavisin’s victory, with 482 votes out of 727 politicians present, ended months of suspense, legal wrangling and horse trading that followed the May elections.

The progressive Move Forward party, which won the most votes in the national election, was blocked from taking power by conservative senators.

Mr Thaksin’s return was an emotional moment for supporters of the 74-year-old billionaire, who won the loyalty of millions with populist policies that directed attention, and funding, to the country’s largely rural, often impoverished, north.

Hundreds of people gathered outside Don Mueang International Airport in Bangkok early on Tuesday morning, donning red clothes and holding signs with welcoming messages.

They sang and chanted in anticipation, then raised a raucous cheer when he appeared at the terminal door.

Makawan Payakkae, a 43-year-old from north-eastern Maha Sarakham province, said: “I feel fulfilled that I travelled here today to pick him up. If possible I want to hug him. Everyone has tears, tears coming out of their eyes.”

Mr Thaksin and parties he backed struggled with the military for years.

He left Thailand 15 years ago, following a 2006 coup that cut short his second term as prime minister and sparked years of upheaval.

A Pheu Thai government led by Mr Thaksin’s sister, Yingluck Shinawatra, was ousted in 2014 by then-army chief Prayuth Chan-ocha, who is now the outgoing prime minister after voters largely rejected military-linked parties.

Mr Srettha will lead a coalition of 11 parties that includes two pro-military parties affiliated with Mr Prayuth, while Move Forward was excluded from the coalition.

Critics called the new government a betrayal of the election results, but Pheu Thai leaders defended it as a necessity for ending the political deadlock and creating reconciliation.

Pheu Thai said Move Forward’s stance on changing the royal defamation law had made it impossible to rally enough support from other parties and the Senate.

Both houses of Parliament vote together for the prime minister under the military-implemented constitution, in an arrangement designed to protect conservative military-backed rule.

Before his return on Tuesday, Mr Thaksin said the decision had nothing to do with the Pheu Thai party’s bid for power, but many observers suspected he is betting that a friendly government will be able to reduce his sentence.

Napon Jatusripitak, a political science researcher and visiting fellow at Singapore’s ISEAS-Yusof Ishak Institute, said: “Thaksin’s plans to return to Thailand were postponed after the election results were announced – this implies a strong connection between the election, formation of coalitions, and selection of the prime minister on one hand, and Thaksin’s personal agenda on the other.”

Less than a week before the May elections, Mr Thaksin announced plans to return before his birthday in July, but they were repeatedly delayed.

Mr Napon said Mr Thaksin’s decision to return now suggests that “he has received assurances that he will not have to serve a prison sentence in full”.

Deputy Prime Minister Wissanu Krea-ngam, of the outgoing military-linked government, has said Mr Thaksin can request a royal pardon like any other inmate, and could receive special consideration because of his age.

After walking out of the airport, Mr Thaksin bowed before a portrait of Thailand’s king and queen and left a flower wreath. He spent a moment greeting supporters and the media waiting in front of the terminal, but did not speak.

His convoy travelled from the airport to the Supreme Court, where a special body that handles criminal cases against former officeholders confirmed an eight-year sentence given to him in absentia for corruption, which he has he dismissed as politically motivated. He then went directly to Bangkok’s main prison.

Correctional officers at Bangkok Remand Prison said in a news conference that, following a medical check, Mr Thaksin had been categorised as “vulnerable” due to his age and chronic conditions affecting his heart and lungs, including high blood pressure. He will be held in isolation and monitored at all hours due to safety and health concerns.

Mr Thaksin’s daughter, Paetongtarn Shinawatra, a key figure in Pheu Thai, posted family photos with him in the middle on Facebook, along with a message thanking people who went to the airport to welcome her father, saying “me and my family are very grateful”.

Pheu Thai said it will control eight Cabinet posts and nine deputy Cabinet posts. The military-backed parties – Palang Pracharath and United Thai Nation – will receive two Cabinet posts and two deputy posts each. Pheu Thai has not identified the ministries that each party will control.

It said the coalition has agreed to support Pheu Thai’s platform of boosting the economy, increasing the minimum wage and ending mandatory conscription.

The parties will also support the continued legalisation of medical marijuana and work to amend the constitution to make the country “become more democratic,” while not touching the royal defamation law, Pheu Thai said.