TOKYO — Momentum appears to be building for Japan's Prime Minister Shinzo Abe to call an early general election, as speculation swirled that he would also postpone an unpopular sales tax hike and his coalition partner urged his party to prepare for a poll. Media reports on Tuesday said Abe might call a snap election before the end of the year if he decides to delay a planned hike in the sales tax to 10 percent from next October. No election for Parliament's lower house need be held until 2016. “There are a lot of different reports building up in the media,” Natsuo Yamaguchi, leader of junior ruling coalition party the Komeito, told a news conference. “We need to consider a posture to cope with that.” The Yomiuri newspaper reported on Tuesday that Abe might dissolve the lower house as early as next week, calling an election for next month, possibly Dec. 14. A government source said that a snap election within the year was one option being considered, while an opposition party source put the probability of an early vote at 90 percent. “If Abe doesn't call an election now, he will lose credibility,” the opposition source said. Abe surged to power in December 2012, promising to revive the economy with his triple “Abenomics” recipe of hyper-easy money policy, fiscal spending and structural reform. But a sales tax hike to 8 percent from April, part of a two-stage plan to rein in huge public debt, sent the economy into a slump and recovery has been less robust than officials hoped. Abe's ratings took a hit from a series of recent money scandals in his Cabinet, and some political insiders said he might want to call the snap election before they slide further. “Everyone thought the election would be next autumn but before that, Abe must tackle several unpopular policies,” the LDP lawmaker added, citing plans to restart nuclear reactors that went off line after the 2011 Fukushima disaster and proposed legal changes to ease curbs on Japan's military. “If he waits and dawdles, he might have to call the election when his support rates are even lower.” A survey by NHK public TV released on Monday showed support for Abe slid 8 percentage points to 44 percent, the lowest since he returned to power for a rare second term. Momentum for the snap vote might now be unstoppable, said veteran political analyst Minoru Morita. “Politicians have begun to believe there will be an election, and this is a big change that will be hard to stop,” he said, adding that Abe's close aides were pushing for the early poll as his best shot for a long tenure in office. — Reuters