Former finance minister Korn Chatikavanij on Sunday announced he had resigned as the leader of the Chartpattanakla Party and would go on holiday with his family.
Mr Korn wrote on Facebook that last week he met party chairman Suwat Liptapanlop and informed the latter of his resignation decision.
He wrote that he was grateful for people's votes for the party and he, as a citizen, would support all the policies the party had proposed. Chartpattanakla won two House seats in the May 14 general election.
Mr Korn wrote that he was greatly honoured to have worked for the people and nation that he loved in his capacity as an elected politician over the past 18 years. He thanked all those who had supported his political endeavours.
He said he was lending moral support to all politicians, especially those who would start their work in parliament.
"Do not be overly obsessed with your desire for victory and acclaim. Work collectively to be a positive force in society. I will send moral support," Mr Korn wrote.
Mr Korn became the leader of the Chartpattanakla Party in October last year, a month after he joined the party.
After the May 14 election, the election-winning Move Forward Party reversed its decision to include Chartpattanakla in its coalition movement.
Mr Korn was finance minister from Dec 20, 2008 - Aug 9, 2011 in the Democrat-led government with Abhisit Vejjajiva as prime minister.
In January 2020 he resigned as a Democrat Party member to set up the Kla Party, with himself as leader. He then jumped ship and joined the Chartpattana Party, which has been renamed Chartpattanakla.