[TOKYO] Japanese Prime Minister Yoshihide Suga is set to replace an unpopular long-term ally as he seeks to shore up support ahead of a party leadership election he must win before the general election planned for October, media said on Tuesday.

Liberal Democratic Party (LDP) Secretary General Toshihiro Nikai told Mr Suga he would step down at meeting on Monday, the reports said.

"I've been in the Secretary General post for more than five years, I want you to do the reshuffle without hesitation," Mr Nikai told Mr Suga, according to the public broadcaster NHK.

Mr Suga's move came as a surprise because Mr Nikai was instrumental in helping him become the prime minister last year.

Mr Nikai was also the first among LDP faction chiefs to throw his group's support behind the premier in this year's contest.

But some parliamentarians have voiced their unease with the amount of power wielded by Mr Nikai, 82, who has held the key LDP post, with control over campaign funds, since August 2016 - the longest in the party's history.

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Mr Suga's rival for the party leader, former foreign minister Fumio Kishida, sparked ire from Mr Nikai after he proposed limits on executive posts and promised to promote young and middle-level lawmakers over heavyweights last week.

The proposal was seen as Mr Kishida's bid to attract grassroots LDP members who, unlike last year, will vote along with members of parliament and who, fearful of losing their seats, may be wary of following their elders' orders.

The reshuffle of the party executive, including Mr Nikai, was set to take place next week, the Kyodo news agency reported.

Mr Nikai and Mr Suga were slated to meet again on Tuesday afternoon.

PARTY GRANDEES

Mr Suga's move may help him secure the backing of other party grandees, such as his predecessor Shinzo Abe and Finance Minister Taro Aso, who have not commented publicly on the race.

"If Suga pledges to drop Nikai, the race is probably over. Guessing that would be followed by firmer expressions of support from Abe and Aso," Tobias Harris, senior fellow for Asia at the Centre for American Progress, said in a tweet.

The winner of the contest is all but assured of being the premier due to the LDP's majority in the lower house and will guide the party through a general election, with the government considering a plan to hold the poll on Oct 17.

Whoever leads the party in the election will face an uphill battle.

Mr Suga's support ratings are at record lows as he failed to capitalise on delivering the Olympics for the country, being hit hard by a fresh wave of coronavirus infections.

The government has declared a fourth state of emergency in most of Japan amid a sluggish vaccination rollout.

An opinion poll on Monday showed Mr Suga's possible rivals for the LDP leader job, such as Administrative Reform Minister Taro Kono, in charge of Japan's vaccination push, and former defence minister Shigeru Ishiba, were more popular.

Both Mr Kono and Mr Ishiba have not decided whether to run.

The LDP and its allies is not expected to lose their coalition majority in the powerful lower house, but forecasts suggest that Mr Suga's party could lose its outright majority, an outcome that would weaken whoever is leading the LDP.

REUTERS