Japanese Prime Minister Sanae Takaichi dissolved parliament on Friday ahead of a snap election on February 8, counting on her cabinet's high poll numbers to steer her otherwise unpopular ruling party to victory.

The country's first woman premier had announced her intentions on Monday, seeking public backing for measures to shield households from rising living costs and increase spending on defence.

The speaker of parliament on Friday read out a letter, officially dissolving the lower house as lawmakers shouted the traditional rallying cry of "banzai".

The ruling coalition of Takaichi's Liberal Democratic Party (LDP) and the Japan Innovation Party (JIP) has only a slim majority in the powerful lower chamber.

Takaichi is hoping widespread support for her cabinet will help deliver her a stronger mandate even though the LDP itself is battling low approval ratings and a string of scandals.

"It's not clear if high public support for the Takaichi cabinet will actually lead to support of the LDP," said Hidehiro Yamamoto, a politics professor at the University of Tsukuba.

"What the public are concerned about is measures to address inflation."

Public discontent over rising prices largely contributed to the downfall of Shigeru Ishiba, whom Takaichi succeeded in October.

While Japan was long haunted by deflation, it has more recently faced a surge in living costs and a chronically weak yen that has made imports more expensive, with prices for rice more than doubling in mid-2025 and, official data showed on Friday, gaining more than 34 percent in December.

Vowing to address the issue and shore up the world's fourth-largest economy, Takaichi's cabinet approved a record 122.3-trillion-yen budget for the fiscal year from April 2026.

But rivals say dissolving the lower house risks delaying its passage through parliament, with Jun Azumi of the main opposition Constitutional Democratic Party saying it would "sacrifice livelihoods".

If elected, Takaichi has pledged to cut a sales tax on food for a two-year period to "alleviate the burden" on people struggling with inflation.

But Takaichi's "proactive" fiscal spending risks inflating the country's already colossal debt, which is expected to exceed 230 percent of GDP in the fiscal year 2025-26.

Takaichi says the policy is "responsible".

Analysts say the election could be a close battle, but that the opposition's chances of winning remain slim.

"The key could be the voting behaviour of young and middle-aged groups, as was the case in the upper house election" in July, Mizuho Research & Technologies said in a note.

The Takaichi government enjoys around 90 percent support among those under 30, according to a poll published at the end of December by the conservative Sankei Shimbun newspaper and Fuji Television. (AFP)