Thailand's Pheu Thai party said on Wednesday it had formed a "democratic front" with six other parties after a disputed election, claiming the opposition alliance had won a majority in the lower house of parliament and the right to try to form a government.

Thailand awaits the results of its first election since a 2014 coup, with the junta primed to retain its grip on power after a vote that saw its main rival diminished but vaulted a new pro-democracy force into the kingdom's politics.

Foreign observers representing the United Nations fan out across Bangkok and its outskirts to monitor the long-delayed election.

Thais began the nail-biting wait to see whether the ruling junta will return to power as a civilian government, or if pro-democracy parties can triumph against the odds, as polls closed in the country's first general election since a 2014 coup.

Hundreds of thousands of voters across Thailand head out to cast early ballots, a week ahead the country's first general election since a military coup in 2014.

The Thai king's sister, disqualified this week by the country's Election Commission from running for prime minister, apologizes for causing "problems" for the Thai people ahead of next month's election, the country’s first since a 2014 coup.

Thailand's Election Commission disqualifies the sister of the king from running for prime minister, ending a stunning, short-lived candidacy for a populist party after King Maha Vajiralongkorn called the bid "inappropriate".

The Thai Raksa Chart party says it will obey a command from the king blocking the candidacy of Princess Ubolratana for prime minister, in a dramatic reversal only a day after putting her forward for the position.