Dozens of Japanese politicians, possibly including cabinet ministers, are poised to visit a Tokyo shrine condemned by China and Korea as a symbol of Tokyo's militarist past, as it begins its autumn festival this week.

A cross-party group of national lawmakers plans to go to Yasukuni Shrine en masse on Friday as it kicks off the four-day festival.

However, Prime Minister Shinzo Abe, who infuriated Beijing and Seoul by visiting the shrine in December last year, is thought unlikely to go.

He will attend an Asia-Europe summit in Milan set for Thursday and Friday and is believed to have one eye on budding signs of an improved relationship with China, with view to a possible summit on the sidelines of a major international meeting next month.

The parliamentarians' group said it does not know how many will join Friday's visit.

In recent years, dozens of lawmakers have participated in the shrine's spring and autumn festivals as well as the August 15 anniversary of Japan's surrender in World War II.

The 145-year-old Shinto shrine honours some 2.5 million citizens who died in World War II and other conflicts.

But it is highly controversial because war criminals are among their number, including senior figures in the WWII administration, such as General Hideki Tojo, who authorised the attack on Pearl Harbor.

Japan's neighbours view pilgrimages there by high-profile politicians as an insult and a painful reminder of Tokyo's aggression in the first half of the 20th century.

With Abe expected to stay away, eyes will be on his cabinet.

On Tuesday internal affairs minister Sanae Takaichi suggested she would pay homage at the shrine, although not necessarily during the mass visit.

"I have offered my gratitude and respect to the souls (of the war dead) in spring, summer and autumn every year as well as on other occasions," she said.

"I'd like to pay homage when I have time," she told reporters, according to Jiji Press news agency.

Chief Cabinet Secretary Yoshihide Suga downplayed any diplomatic fall-out Takaichi's visit could have.

"Since the start of the second Abe administration, our government's position is that it is an individual decision if a minister visits the shrine in a personal capacity," he said.

"It would be the same in any country that people pay respects to those who died for their country and pray for peace," he said.

Takaichi is politically close to Abe and one of five women who got a portfolio when he reshuffled his cabinet last month.