Prime Minister Shinzo Abe will discuss the ongoing territorial dispute with Russian President Vladimir Putin in Singapore, the first stop of the Japanese leader’s five-day Asia-Pacific tour which begins Wednesday.

The focal point of the summit will be whether Abe can make any progress in negotiations on the dispute over four Russian-held islands claimed by Japan, observers said.

Abe will attend meetings related to the Association of Southeast Asian Nations (ASEAN) in Singapore that will be held between Sunday and Thursday and a summit of the Asia-Pacific Economic Cooperation (APEC) forum in Papua New Guinea on Nov. 17 and 18. He will also visit Australia.

At an economic forum in the Russian Far Eastern city of Vladivostok in September, Putin proposed to sign a peace treaty by the end of this year without setting any preconditions.

When the two leaders watched a judo competition held soon after the forum, Abe told Putin that Japan cannot accept such an offer.

The territorial row has prevented the two sides from concluding a peace treaty to formally end their World War II hostilities. The islands, known as the Northern Territories in Japan and the Southern Kurils in Russia, were seized from Japan by Soviet troops in the closing days of the war in 1945.

After returning home from Vladivostok, Abe said he takes Putin’s abrupt proposal as an expression of his “eagerness” to conclude a peace treaty with Japan, indicating hopes of making progress in negotiations on the territorial dispute at two envisaged summits this year, including the one in Singapore.

But the negotiations could be tough as Putin has not mentioned any intention of making concessions, observers said.

Abe is also arranging meetings with Chinese President Xi Jinping and Premier Li Keqiang, who are expected to participate in the ASEAN and APEC meetings, in hopes of further improving bilateral ties.

South Korean President Moon Jae-in plans to join the meetings as well, but many Japanese government officials are negative about holding a Japan-South Korea summit this time as Seoul has not shown any inclination to correct what Japanese officials see as a violation of international law over the issue of former requisitioned South Korean workers in Japan.

In late October, South Korea’s Supreme Court issued a ruling in favor of such workers in a damages lawsuit.

In Australia, Abe will hold talks with his Australian counterpart, Scott Morrison, to confirm that the two countries will strengthen national security cooperation.

Abe hopes to promote his free and open Indo-Pacific region strategy at the Japan-Australia summit and at other meetings during the tour.