Abhisit Vejjajiva on late Sunday night resigned as the leader of the Democrat Party to show responsibility for the electoral failure of his party.

Mr Abhisit told a brief press conference at the Democrat headquarters at about 9.50pm that it was clear that polling results were different from his targets for House seats' rankings and numbers of his party and he apologised for his failure to present the concepts of his party to pave the way for its success in the election.

He also announced the party's wish to join a government coalition.

"I apologise to the fellows who share ideals, both former MPs and newcomers, for their failure to enter the House. I must take responsibility. Therefore, I resign as the party leader from now on," Mr Abhisit said.

"Thanks to those who have supported me. I will continue my work for the party. I must keep my word," he said.

Earlier, he had announced that he would resign as the party leader if his party won less than 100 House seats.

It was estimated at about 10pm that the party would have 30 constituency MPs.