Japan has proposed to China and South Korea that their long-delayed trilateral summit be held in Tokyo in early April, but Beijing is withholding its response, diplomatic sources said.

Since China is reluctant to hold such a summit before the National People's Congress in March, the government of Prime Minister Shinzo Abe has conveyed its readiness to host a three-day visit to Japan by Chinese Premier Li Keqiang and South Korean President Moon Jae-in from April 4 or April 9, the sources said Friday.

Seoul said it will try to make the necessary arrangements, they said.

The trilateral summit was last held in November 2015. Japan is scheduled to host the next one, but it has been repeatedly postponed by territorial and historical disputes.

Foreign Minister Taro Kono is expected to visit China late next month at the earliest to arrange the summit date. The government hopes to have Abe visit China after the trilateral summit and invite Chinese President Xi Jinping to Japan by the end of 2018.

Government sources have said Abe may not attend the Pyeongchang Winter Olympics in February — despite an invitation from the Moon administration — because of Seoul's dissatisfaction with the 2015 "comfort women" agreement. The accord was intended to permanently resolve the dispute over the girls and women forced into Japan's military brothels before and during the war.

On Wednesday, after a South Korean government task force found flaws in the domestic process that led to the accord it signed with Japan, the Moon administration said it was unable to resolve the longtime dispute. The agreement was signed under Moon's predecessor, Park Geun-hye, who was later impeached.