The party submitted the names of lawmakers to the speaker of the House of Representatives, urging him to call parliament into session to elect the next prime minister at the earliest, the Thai News Agency reported.
The party claimed it has secured the signatures of 260 lawmakers from the 480-member lower house and is ready to form a new government, the report said.
The move comes in the wake of months of anti-government protests leading to the constitutional court dissolving the ruling coalition led by Prime Minister Somchai Wongsawat's People Power Party. The coalition was accused of electoral fraud in December 2007 elections.
That coalition, however, has formed a new party called Puea Thai Party, claiming it, too, has enough support to form the next government, TNA reported.