Japan's parliament has extended its current session as the government tries to push through a law to renew support for a US-led mission in Afghanistan.
Japan's refuelling mission has proved controversial at home
Parliament will now meet well into December in an effort to resolve a stalemate on the issue.
Japan withdrew ships from Afghan naval operations earlier this month because the mandate ran out without a deal.
US defence secretary Robert Gates, who is currently in Tokyo, has encouraged Japan to keep supporting the operation.
Japan's contentious mission involved providing vessels in the Indian Ocean which refuelled and gave logistical support to US military planes.
The mandate to extend the mission expired on 1 November, and the government is keen to extend it.
But critics, including much of the opposition, say Japan's involvement violates the nation's pacifist constitution, which has strictly limited its military activities since the end of World War II.
Disagreement over the issue was one of the main reasons which led Shinzo Abe to resign from his post as prime minister in September, to be replaced by Yasuo Fukuda.
Now lower house lawmakers have voted to extend the parliamentary term for both houses by 35 days to 15 December, instead of adjourning on Saturday.
Within this added timescale, the vote is likely to be passed in the lower house, where Mr Fukuda's Liberal Democratic Party is in the majority.
But the opposition Democratic Party of Japan will probably refuse to back the decision when it goes for ratification in the upper house - where it has a majority.
The bill will finally return to the lower house which is likely to pass it into law despite the heavy disagreement.
Mr Gates has added pressure on Japan to assume a prominent role in world security.
Speaking on a visit to Tokyo, he said Japan had "the opportunity - and an obligation - to take on a role that reflects its political, economic and military capacity".
"That is why we hope and expect Japan will choose to accept more global security responsibilities in the years ahead," he said.