An election must be held 45 to 60 days after the house dissolution, which takes effect immediately.

“This is a return of political decision-making power to the people swiftly to continue democratic government with the King as head of state,” said the decree published today.

An election date has yet to be announced but deputy prime minister Wissanu Krea-ngam earlier in the day said it would likely be held on May 14, if the house were dissolved today.

Thailand’s election is expected to showcase a long-running political battle between the billionaire Shinawatra family and the country’s conservative pro-military establishment.

Paetongtarn Shinawatra, the daughter and niece respectively of ousted former premiers Thaksin and Yingluck Shinawatra, is the frontrunner to be prime minister in opinion surveys, with her support jumping 10 points to 38.2% in a poll released at the weekend.

The poll by the National Institute of Development Administration (Nida) put Prime Minister Prayuth Chan-ocha, who has been in power since a 2014 coup against the Pheu Thai government, in third place with 15.65%.

Paetongtarn on Friday said she was confident of winning the election by a landslide, with the aim of averting any political manoeuvring against her party, which has previously been removed from office by judicial rulings and military coups.