The ruling coalition sought Thursday to extend the current ordinary Diet session by 55 days through Aug. 13, seeking more time to enact contentious postal privatization bills.

Although the current session is scheduled to adjourn Sunday, the postal reform bills have yet to clear the House of Representatives, which has spent about 60 hours deliberating them at a special committee. An ordinary Diet session can only be extended once.

"Many issues, such as the postal privatization bills, have been left pending," Liberal Democratic Party Secretary General Tsutomu Takebe told reporters. "Extending the session is unavoidable, for it is the ruling parties' responsibility to prepare to have (the bills) receive final Diet approval."

Takebe and his New Komeito counterpart, Tetsuzo Fuyushiba, submitted the extension request to Lower House Speaker Yohei Kono and House of Councilors President Chikage Ogi in the afternoon.

The ruling coalition is hoping the extension will be approved by the Lower House on Friday, but the move may be delayed, with the opposition objecting to it.

"We'd like to strongly demand that these imperfect (postal privatization) bills be scrapped and the 150-day session adjourn as scheduled," Yoshio Hachiro, the Democratic Party of Japan's Diet affairs chief, told reporters. "A majority of the people don't want the Diet to hastily approve the bills."

He said the opposition may submit a no-confidence motion against postal privatization minister Heizo Takenaka, citing his failure to attend a Lower House committee session and allegations that an advertising agency run by an acquaintance of a secretary to the minister won a 150 million yen contract with the government to make postal reform leaflets.