Factbox: Main Parties Contesting Japan's Upper House Election

Japan holds an upper house election on Sunday that is key to Prime Minister Fumio Kishida's attempt to gain firmer control of the ruling Liberal Democratic Party (LDP) to enable it and its Komeito junior partner to push through legislation.

Here are key facts about Japan's main political parties.

LIBERAL DEMOCRATIC PARTY

Established: 1955

Website: jimin.jp/english/

Number of upper house seats up for re-election this time: 55

Number of upper house seats up for re-election in 2025: 56

The conservative party has been in power almost continuously since its foundation, either on its own or in a coalition, and has formed close ties with business and the bureaucracy.

Faced with China's maritime expansion and North Korea's missile and nuclear development, the LDP aims to boost defence spending sharply, using a NATO goal of 2% of gross domestic product on defence as a guide.

That would be a departure from Japan's decades-old practice of keeping defence spending at about 1% of GDP but public support for bolstering defence is growing after Russia's invasion of Ukraine.

While opposition parties call for cutting or abolishing a 10% sales tax to help the public cope with soaring food and energy prices, Kishida believes the levy should be maintained to support the ageing country's social security system.

KOMEITO

Established: 1964

Website: komei.or.jp/en/

Number of upper house seats up for re-election this time: 14

Number of upper house seats up for re-election in 2025: 14

Backed by a Buddhist lay organisation, the Soka Gakkai, the Komeito party was a junior partner in LDP-led governments for 10 years until the ruling alliance's election defeat in 2009. But it returned to power with the LDP in a December 2012 lower house election.

Komeito is more moderate on security issues than the LDP and it proposes shaping defence within an exclusively defensive security policy. The party seeks to promote the interests of the less well-off when it comes to economic policy.

CONSTITUTIONAL DEMOCRATIC PARTY OF JAPAN (CDPJ)

Established: 2020

Website: cdp-japan.jp/english

Number of upper house seats up for re-election this time: 23

Number of upper house seats up for re-election in 2025: 22

The centre-left CDPJ is Japan's largest opposition party. Its roots lie in the Democratic Party of Japan, which succeeded in defeating the LDP-Komeito alliance in 2009 and held power for three years.

As part of measures to respond to surging prices, the party calls for temporarily cutting the sales tax by half to 5% and offering 10,000 yen ($73) a month as a subsidy to house renters.

It advocates investing 200 trillion yen in renewable energy and energy conservation by 2030 and cutting greenhouse gas emissions by 55% or more from 2013 levels. That is more ambitious than the government's target of reducing the emissions by 46% by 2030.

In a poll by Kyodo news agency, 28.3% of those surveyed said they would vote for the LDP in the proportional representation part of the July 10 election, followed by the CDPJ's 8.2% and Komeito's 7.2%.

JAPAN INNOVATION PARTY (JIP)

Established: 2015

Website: o-ishin.jp/ (Japanese only)

Number of upper house seats up for re-election this time: 6

Number of upper house seats up for re-election in 2025: 9

The reformist party saw nearly a fourfold jump in the number of its seats in the lower house election in October. It hopes to maintain that momentum in the upper house vote and nip at the heels of the CDPJ, its larger rival in the opposition camp.

The JIP joins the ruling LDP in calling for a sharp increase in defence spending and a constitutional revision to make a specific reference to the Self-Defence Forces (SDF), as Japan calls its military.

The charter, if taken literally, bans a standing military, prompting some academics to question the SDF's legality.

JAPANESE COMMUNIST PARTY (JCP)

Established: 1922

Website: jcp.or.jp/english/

Number of upper house seats up for re-election this time: 6

Number of upper house seats up for re-election in 2025: 7

The political party with the longest history in Japan, the JCP celebrates its 100th anniversary this year.

The party opposes the LDP's plan to boost defence spending substantially and warns that military expansion would only invite an arms race in the region, escalating tension.

DEMOCRATIC PARTY FOR THE PEOPLE (DPFP)

Established: 2000

Website: new-kokumin.jp/ (Japanese only)

Number of upper house seats up for re-election this time: 7

Number of upper house seats up for re-election in 2025: 5

Seeing human resources development as key to economic growth, the party calls for free education up to high school and the issuing education bonds to double the budget for education, science and technology to 10 trillion yen a year.

($1 = 136.2900 yen)