South Korean Foreign Minister Yun Byung-se will visit Japan this weekend for the first time since taking office, Tokyo said Wednesday, as the two countries mark 50 years of diplomatic relations.Yun will meet his Japanese counterpart Fumio Kishida on Sunday to discuss the bilateral relationship, North Korea and other topics, the foreign ministry said.

He will also attend a ceremony Monday at the South Korean Embassy to celebrate half a century since relations between Tokyo and Seoul were normalized, it said.

Japanese Prime Minister Shinzo Abe may also attend the embassy event, according to media reports.

Yun and Kishida held talks in March in Seoul, but Yun has not been to Japan since being appointed in 2013. Relations have been severely strained by rows over history and territory.

Abe has made numerous offers overture to South Korean President Park Geun-hye, offering to hold summits, but has been rebuffed since the two came to power in late 2012 and early 2013 respectively.

Park has said there can be no meeting until Japan makes amends for its wartime system of sex slavery, which saw as many as 200,000 mostly South Korean "comfort women" forced into servitude for Japan's Imperial military.

Japan maintains that the issue was settled in the 1965 normalization agreement, which saw Tokyo make a total payment of $800 million in grants or loans to its former colony.

The money funded the establishment of South Korea's steel industry, among a variety of other development projects.

The Japanese government also issued a formal apology in 1993, which remains the official policy.

There have been some discussions on the issue over the past 12 months, although both sides appear to have hardened their positions in recent years.

Park said during a recent interview with The Washington Post that "there has been considerable progress on the issue of the comfort women" and the two countries are "in the final stage" of their negotiations.

"We can expect to look forward to a very meaningful 50th anniversary of the normalization of our diplomatic ties," she said.

However, Yun appeared to row back a little from that rosy assessment Monday, telling reporters in the US there must be more effort to resolve the issue, according to Jiji Press.

Japan and South Korea are also at odds over ownership of the sparsely-populated Dokdo islets, which sit in the Sea of Japan and are controlled by Seoul. Tokyo claims them under the name Takeshima.