Japanese Prime Minister Shinzo Abe should make a determination to embark on sincere negotiations with South Korea over the resolution of Tokyo's wartime sex enslavement of Korean women, a former Japanese premier said Thursday.

Tomiichi Murayama made the remarks a few days before the leaders from South Korea and Japan will hold their first summit in more than three years next Monday amid diplomatic tension over Japan's sex slaves during World War II.

Murayama said that Abe should lead Seoul and Tokyo in making diplomatic efforts that address the issue.

"(Seoul and Tokyo) could find a solution to the issue if they are to hold genuine negotiations," Murayama told a forum on global peace in Seoul.

Since taking office in early 2013, President Park Geun-hye has shunned a summit with Abe, citing Japan's refusal to apologize for Tokyo's wartime wrongdoings. It is not clear how sincerely Abe would deal with the issue at the bilateral summit.

"As Park has strongly called for the resolution of the issue, there has been no summit between them for a long time," he said.

"The Seoul-Tokyo relations have been also frayed. ... The two leaders have a responsibility for making a breakthrough."

The issue warrants urgency as the number of former South Korean sex slaves has dropped to 47 with their average age standing at nearly 90.

Murayama said Abe's statement issued in August was "too vague" compared with his 1995 statement stating Japan's apology for its 1910-45 colonial rule of the Korean Peninsula. Abe stopped short of a direct apology for his country's wartime deeds.

The so-called Murayama Statement has been regarded as a key element of the basis of relations between Seoul and Tokyo, along with Japan's 1993 landmark "Kono Statement" apologizing for its wartime sexual slavery.

"Abe needs to clarify whether he has sincerity in apologizing for Tokyo's wartime acts," said Murayama, who served as Japan's prime minister from 1994 to 1996. (Yonhap)