BANGKOK (REUTERS) - Thailand's Constitutional Court on Thursday (March 7) dissolved the opposition Thai Raksa Chart party for nominating the king's sister as its candidate for prime minister ahead of this month's election.

Thai Raksa Chart is one of several parties loyal to ousted former prime minister Thaksin Shinawatra in the March 24 election that broadly pits his supporters against establishment parties, including one that has junta leader Prayut Chan-o-cha as its prime ministerial candidate.

The Election Commission had asked the court to dissolve the party after it nominated Princess Ubolratana for prime minister, which the commission described as "antagonistic toward the constitutional monarchy".

The princess relinquished her royal titles in 1972 but is still officially treated as a senior member of the royal family, which is highly revered in Thailand.

King Maha Vajiralongkorn strongly opposed his sister's nomination, calling it "inappropriate" and unconstitutional and her candidacy was swiftly disqualified by the Election Commission.

Disqualifying the Thai Raksa Chart party would strike a blow to opposition parties' chances of winning the general election and defeating parties allied to the military junta that has ruled Thailand since a coup d'etat in 2014.

New electoral rules put in place by the outgoing military government benefit smaller parties at the expense of the top vote-winning parties when 150 "party seats" are shared out in the 500-seat House of Representatives.

Police deployed more than 1,000 officers in and around the court and cordoned off the surrounding area ahead of the ruling.