The leader of Thailand's main opposition Democrat Party says he will resign after his party's crushing defeat to Prime Minister Thaksin Shinawatra's Thai Rak Thai party.

Banyat Bantadtan told reporters Monday that he would be replaced by a deputy party leader until the election of the next leader.

Mr. Bantadtan conceded defeat Sunday as exit polls projected Mr. Thaksin's party winning 399 of the 500 seats in Parliament.

If the result is confirmed in an official tally due Monday, it would give Mr. Thaksin a landslide historic second victory, paving the way for him to form a single-party government.  Even if all opposition parties banded together, they would not have enough seats to pass a no-confidence vote in Parliament.

Some information for this report provided by Reuters, AFP.