TOKYO (Reuters) - Japanese political heavyweight Ichiro Ozawa and dozens of other members of parliament who quit the ruling party in protest over a planned sales tax increase decided on Wednesday to form a new party in a move likely to add to the government's headaches.
About 50 defectors from the ruling Democratic Party of Japan (DPJ) are expected to join the party when it is launched on July 11, a lawmaker close to Ozawa said.
The departure of Ozawa and his followers reduces DPJ seats in the 480-member lower house to about 250 - the numbers keep changing as members flip-flop - allowing the government to keep its majority in the powerful chamber.
Still, Ozawa - known as the "Destroyer" for his record of wrecking political parties he creates - will wield some political influence and be a nuisance for Prime Minister Yoshihiko Noda, analysts said.
The new party could submit a non-binding but embarrassing censure motion against the prime minister in the upper house, which would be passed if other opposition parties follow suit.
"I still think Ozawa may be a factor. Nobody plays with Ozawa because they like him. They play with him because they have to," said Koichi Nakano, a Sophia University professor.
Ozawa, credited by some with masterminding the Democrats' sweep to power in 2009, says the plan to double the sales tax to 10 percent by late 2015 violates a party campaign pledge.
The bill, aimed at curbing bulging public debt, was passed by the lower house last week with the help of the opposition and is expected to gain approval in the opposition-controlled upper house as well.
(Reporting by Tetsushi Kajimoto; Editing by Linda Sieg)