Japan\'s centre-left government Wednesday pushed through an extension of the parliamentary session, but the threat of paralysis loomed amid bitter debate on when Prime Minister Naoto Kan will resign. Kan pledged this month to step down soon, but he has also demanded that bills on reconstruction from the March 11 quake, tsunami and nuclear disaster are passed first, along with legislation to promote renewable energy sources. The main conservative opposition Liberal Democratic Party (LDP), however, has threatened to block all key bills until Kan resigns -- setting the stage for a tense standoff and more political turmoil in coming weeks. Senior members of Kan\'s Democratic Party of Japan (DPJ) have also asked the premier to step down to avoid political gridlock in the world\'s third-largest economy, already burdened with sluggish growth and a public debt mountain. The LDP -- which was ousted in a landslide election in 2009 after more than half a century of almost unbroken rule -- has accused Kan of bungling the recovery effort and rejected offers of a grand coalition government. Amid the political skirmishing, which has dismayed voters in the disaster-hit nation, the DPJ-dominated lower house voted Wednesday to extend by 70 days its current session, which had been due to end that day. The DPJ and its coalition partners plan to use to the time to pass another bill on rebuilding the disaster areas, as well as a bill to issue bonds for the current fiscal year to help pay for the recovery efforts. Kan -- who started his political life as an environmental campaigner -- also wants to pass a bill to promote renewable energy, having pushed for a rethink on atomic power since the Fukushima Daiichi nuclear plant disaster. The turmoil escalated on June 2, when Kan defeated an opposition no-confidence motion, initially backed by DPJ rebels, by pledging to step down once the recovery takes hold, but without giving a firm date. The move helped Kan, Japan\'s fifth premier in as many years, to stay in power for now, but set off feverish speculation on when he would step down. Finance Minister Yoshihiko Noda has emerged as a frontrunner to take his post.