TOKYO - Japan's new prime minister will be selected at a special session of the Diet on December 26 at the earliest, Japan's Kyodo reported Tuesday.

The new prime minister would form a cabinet immediately to replace the existing one ?led by current ruling Democratic Party of Japan and continue its duties,the report said.

No matter which party wins the House of Representatives election, Prime Minister Yoshihiko Noda has to convene the special session, which is likely to last three days, so as to elect a new prime minister.

The opening day of the session was initially set on December 26, but may be pushed back to December 27 or later depending on coordination among major parties, the report said.

According to latest poll, Japan's main opposition party, the Liberal Democratic Party headed by former Prime Minister Shinzo Abe, is expected to win majority in the general election along with its ally, the New Komeito Party.

The lower house was dissolved by Prime Minister Yoshihiko Noda on November 16 and the general election will be held on Sunday.