Thai Prime Minister Prayuth Chan-ocha on Tuesday said he would dissolve parliament next month ahead of an election that would likely take place on May 7, a potential date previously outlined by the country's poll body.

The former army chief, who has been in power since he led a coup in 2014, said the election commission needed until the end of this month to agree on a timeframe, while house dissolution in March would be sufficient time for candidates to prepare.

Asked by a reporter if the election would be on May 7, Prayuth said: "Sure, why not?"

Campaigning is already underway in Thailand for an election that could upset the status quo after nearly nine years of government led or controlled by the military and its backers in the royalist establishment.

Opinion polls on the top choice for next leader show Prayuth, 68, trailing political newcomer Paetongtarn Shinawatra, the 36-year-old daughter and niece of two former prime ministers elected in landslides but toppled by the army.

Paetongtarn will represent the opposition Pheu Thai, the latest incarnation of a party controlled by the billionaire Shinawatra family, which has won the most votes in every election since 2001.

Prayuth, who leads a 17-party coalition government, has switched to the new United Thai Nation party (UTN), while his military mentor and deputy prime minister, Prawit Wongsuwan, 77, will represent the ruling Palang Pracharat party.

Government spokesperson Anucha Burapachaisri on Tuesday presented a rough timeline for an election likely in early May, with results announced in early July.

The new legislature would choose a prime minister by the end of July and name their cabinet in early August, with Prayuth's government serving as caretaker in the interim, Auncha told a news conference.

- Reuters