Three main candidates, out of 21 in total, are contesting this Sunday's election to become Tokyo's next governor.

YURIKO KOIKE, 64 Ms Koike is a former lawmaker of the ruling Liberal Democratic Party (LDP) and is running as an independent candidate after failing to win the party's blessings.

Fluent in Arabic and English, she worked as a translator and then news anchor. Served as defence and environment minister. Key campaign pledges: Set employment targets for women, solve day-care centre shortage, improve elderly nursing care, increase aid for children living below the poverty line. Appeal to voters: Potentially Tokyo's first female governor, without the shackles of a political party. Has been christened Tokyo's "Joan of Arc". HIROYA MASUDA, 64 Governor of Iwate prefecture in north-east Japan from 1995 to 2007; he was then appointed internal affairs and communications minister, a post he held until September 2008. In 2014, he headed a Japan Policy Council think-tank panel that raised the alarm over the population flow from rural areas into large cities.

Backed by the LDP, its coalition partner Komeito, and the Party for Japanese Kokoro. Key campaign pledges:A critic of Tokyo's overpopulation. Calls for decentralisation to reduce the rural-urban income gap. Has vowed to solve shortage of workers in child day-care centres and to support the elderly. Appeal to voters: Backed by the ruling LDP government; vast administrative experience.

SHUNTARO TORIGOE, 76 Former journalist based in Iran in the 1980s, reporting on the Iran-Iraq War. He is backed by four opposition parties, including the Democratic Party and Japanese Communist Party. Key campaign pledges: Has called for a review of this year's Budget dealing with the ageing society and low birth rate. The cancer survivor has also proposed universal cancer screening for adult residents. Appeal to voters: A long-time critic of Prime Minister Shinzo Abe's policies; will be favoured by those against the LDP.

Walter Sim