TOKYO, Sept 2 (Reuters) - Three candidates are vying to become the next leader of Japan's ruling Liberal Democratic Party (LDP) after outgoing Prime Minister Shinzo Abe said last week he would step down for health reasons.

The next president of the LDP is virtually assured of being prime minister because of the party's majority in parliament's lower house.

Here are some of the main policy stances of Chief Cabinet Secretary Yoshihide Suga, former Defence Minister Shigeru Ishiba and former Foreign Minister Fumio Kishida:

YOSHIHIDE SUGA

A longtime lieutenant of Prime Minister Shinzo Abe, Suga has secured the backing of five of the LDP's seven factions, local media said, positioning himself as a clear favourite.

ECONOMY

Suga is expected to stay the policy course set out by Abe, including the "Abenomics" strategy aimed at reviving the economy as well as post-pandemic fiscal stimulus.

Suga opposes lowering the 10% sales tax rate, which he sees as indispensable to social security reforms. Some lawmakers have proposed lowering the tax to reduce the burden of the pandemic on households.

He is a strong promoter of tourism as a way to drive local economies and signalled in a recent interview with Reuters the importance of re-opening the economy over tighter pandemic restrictions.

As such, he also told Reuters in a recent interview that Japan would do "whatever it takes" to ensure it could host the Olympics next year.

He favours greater consolidation of regional banks and wants mobile phone carriers to lower fees.

DIPLOMACY, SECURITY

Suga believes Japan should review its security strategy within the boundary of the U.S.-drafted pacifist constitution.

He regards Japan's alliance with the United States as the core of Tokyo's diplomacy and security.

On China's move in June to pass national security legislation for Hong Kong, he said it was "regrettable" and undermined the credibility of the "one country, two systems" formula.

FORMER DEFENCE MINISTER SHIGERU ISHIBA

A rare LDP critic of Abe, Ishiba regularly tops surveys of lawmakers whom voters want to see as the next premier, but is less popular with party heavyweights.

ECONOMY

Ishiba has praised "Abenomics" for helping boost share prices and drive corporate profits, but says people with low income, small companies and rural areas have been left behind.

He recognises the importance of sales tax as a stable revenue source to fund social security programmes, but says the government should look into ways to soften the impact of the tax on low-income households.

DIPLOMACY, SECURITY

Like Suga, Ishiba considers ties with the United States to be the cornerstone of Japan's diplomacy and security.

He also favours deepening ties with Asian neighbours, including South Korea, amid growing tension between China and the United States.

"We must build political, cultural or security relationships of trust with Asia," he told Reuters this week.

FORMER FOREIGN MINISTER FUMIO KISHIDA

Kishida served as foreign minister under Abe from 2012 to 2017, but diplomacy remained mainly in the prime minister's grip. He ranks low in voter surveys.

ECONOMY

He believes the Abenomics mix of hyper-easy monetary policy and government spending should be maintained and on Wednesday told Reuters that for the next few years, Japan must take bold fiscal steps to combat the pandemic.

DIPLOMACY, SECURITY

Kishida hails from one of the party's more dovish factions and is seen as less keen on revising the post-war constitution's pacifist Article 9 than Abe, for whom it was a cherished goal.

He told Reuters that Japan needed to have frank discussions with the United States over the defence burden and that Japan must take a strong stance against Chinese moves to change the regional situation. (Reporting by Izumi Nakagawa, Kiyoshi Takenaka; Editing by David Dolan and Gerry Doyle)