Prime Minister Yoshihiko Noda kicked off a new Diet session Tuesday by urging the opposition camp to stop playing party politics and join talks on raising the consumption tax.

The biggest and most difficult task Noda has on his plate during the 150-day Diet session is to pass legislation to hike the 5 percent consumption tax to fund the swelling social security costs of the rapidly aging society.

But the Liberal Democratic Party, the largest opposition force and one that earlier said a tax hike to 10 percent was necessary, has refused to hold discussions and is pressing Noda to dissolve the Lower House and call an election first.