Okyo: Japan's justice minister resigned on Monday over comments that made light of his duty to respond to questioning in parliament, a blow to the ruling Democratic party as it struggles to keep Japan's fragile economic recovery alive.

Minoru Yanagida said on November 14 that as justice minister he only needed to remember two comments when facing questions from lawmakers: "I do not comment on specific cases," and "We are dealing with the matter appropriately based on law and evidence."

The remarks set off a firestorm of criticism from lawmakers, who demanded he step down from his post. The gaffe is the latest setback for Prime Minister Naoto Kan, whose plunging support in opinion polls has emboldened the political opposition.

The resignation doesn't threaten Kan's grip on power, but is likely to further erode public support for an administration already facing anger over his perceived weakness in handling recent diplomatic spats with China and Russia.

The political sparring in parliament has delayed progress on a $61 billion financial stimulus package, even as deflation and a strong yen threaten the struggling economy.

"It is my fault that I made those imprudent and joking comments, and I must apologise deeply," Yanagida said on Monday during a press conference to announce his resignation.

He said he decided to step down after meeting early on Monday with Kan, who expressed concern about the debate holding up passage of the stimulus package, which includes financial support for small businesses and local economies. Over the weekend, Yanagida had said he intended to keep his post, despite the criticism.

The main opposition party had been preparing a censure motion against him and threatening to boycott parliamentary deliberations on the stimulus budget if he didn't quit.

Chief Cabinet Secretary Yoshito Sengoku will take over as justice minister until a new candidate is found.

"Our Cabinet will buckle down and sincerely respond to parliamentary affairs so that we will not repeat a similar problem," he said.

Passage of the stimulus package is almost guaranteed because the ruling Democrats control the more powerful lower house. And even if the opposition-controlled upper house rejects the package, it will become law within 30 days.

Many voters feel Kan's government responded too timidly in recent rows with China and Russia over disputed islands. And parliamentary debate over the stimulus package has been held up over Kan's handling of leaked video footage of a September collision between a Chinese fishing boat and Japanese patrol vessels in disputed waters that sparked the spat.

Japan's economy expanded at an annualised pace of 3.9 per cent in the third quarter, but all signs point to a rapid deceleration in the current quarter. Slowing exports and a persistently strong yen are taking their toll, while deflation is keeping a tight grip on the world's No. 3 economy.

Support for the current administration sank to 26 per cent from 49 per cent a month earlier, in a voter poll taken over the weekend by the national Mainichi newspaper. Of those polled, 71 per cent said they thought Yanagida should resign.

Such opinion polls are quite influential in Japan and in the past have put enormous pressure on administrations.

The survey was done on 989 eligible voters using a method based on a random telephone survey. The paper did not provide a margin of error, but a poll of that size would generally have a margin of plus or minus five per cent.