The Democratic Party of Japan will wait until Prime Minister Junichiro Koizumi returns from a Group of Eight summit in the United States this week before submitting a no-confidence motion against his Cabinet, DPJ chief Katsuya Okada said Monday.

The prime minister is scheduled to participate in the annual G8 summit at Sea Island, Ga., from Tuesday to Thursday. He is to return home Saturday.

Okada hinted, however, that the DPJ may submit a no-confidence vote against Koizumi next week, before the current Diet session adjourns June 16.

He urged the ruling coalition to take responsibility for forcing a package of controversial pension bills through the Diet last weekend.

Diet proceedings have ground to a halt since the pension bills were enacted Saturday — two days after the ruling coalition rammed the bills through a House of Councilors committee.

The legislation was approved by the Upper House plenary session after Upper House President Hiroyuki Kurata put the bills to a vote in the absence of DPJ and Social Democratic Party members.

“With the (Diet) situation as it is, I understand that we do not have the option of not filing a no-confidence motion (against the Koizumi Cabinet),” Okada told reporters after discussing the DPJ’s strategy for the rest the Diet session with fellow party executives.

“But we should refrain from submitting such a motion” just as the annual G8 summit is to be convened, he said.

Okada went on to explain that the DPJ must not act in such a way that would put the prime minister at a disadvantage diplomatically when he is to hold negotiations with other G8 leaders.

Meanwhile, the Liberal Democratic Party and its coalition partner, New Komeito, expressed determination to have the Upper House enact pending bills before the Diet, including a set of seven war contingency-related bills.

“We’d like the Upper House to deal with 30 remaining items, including the three bills that will be sent from the Lower House on Tuesday, by the end of the current session,” said a senior coalition lawmaker in charge of Diet affairs.