SEOUL  - South Korea and Japan on Wednesday vowed to work closely together on North Korea ahead of the looming inter-Korea summit, but their foreign ministers remained divided over long-standing issues of Japan's wartime crimes and disputed islands. 

Japanese foreign minister Taro Kono made a rare visit to Seoul armed with a list of issues Tokyo wants to push onto the agenda of the April 27 summit between North and South Korea. 

At a time of frenetic diplomatic activity in northeast Asia - the North's Kim Jong Un is due to meet with the leaders of both South Korea and the US - Japan has largely remained on the sidelines. 

Tokyo has found itself forced to rely on the US and South Korea to tackle its concerns regarding the North, which last year test-fired several missiles that flew over Japan, sparking security fears. 

Kono and his South Korean counterpart Kang Kyung-wha vowed "close communication and cooperation" to disarm the North and build peace on the flashpoint peninsula, Seoul's foreign ministry said after their meeting in Seoul. 

The Japanese envoy also met with President Moon Jae-in, who said working together on North Korea was "more important than ever" ahead of the summits, the South's Yonhap agency reported. It was the first visit to South Korea by a Japanese foreign minister in more than two years. 

But the top diplomats remained divided on two thorny historical issues still unresolved. The hugely emotional matter of Korean women forced into sexual slavery for Japanese troops during World War II has soured ties between the South and Japan for years. 

Seoul has urged Tokyo to take legal and moral responsibility, while Japan says that the issue was resolved when the two nations reached a deal in 2015 to offer compensations to the victims. 

South Korea and Japan have also locked horns over Seoul-controlled islets in the sea between the two countries called Dokdo in the South and Takeshima in Japan. "Kono expressed Japan's stance on 'comfort women' and Dokdo, and Kang explained our stance over 'comfort women' and made clear that the South cannot accept any argument by Japan over Dokdo," the ministry said in a statement. 

Moon said last month that Japan cannot unilaterally declare the wartime issue "over," while Japan says any attempt to modify or scrap the deal, signed by Moon's predecessor Park Geun-Hye, could hurt relations. 

Kono, before the Seoul visit, also said he would try to ensure that the "abduction issue will be talked about in the North-South summit", as well as Pyongyang's "nuclear and missile issues". 

He was referring to Japanese citizens abducted by the North's agents in the 1970s and 80s in a bid to train spies in Japanese language and customs before overseas missions. 

But a statement on the meeting from Seoul's foreign ministry did not mention the topic - a key issue in ties between Japan and the North, which habitually spats out angry threats of attack against "Japanese reactionaries." 

Chinese official, art troupe to attend N Korea festival 

China will send a Communist Party official with an art troupe to North Korea for a festival celebrating the country's founder, state media said Wednesday, as the neighbours seek to heal battered relations.  

The delegation will leave on Friday to attend the April Spring Friendship Art Festival at the invitation of North Korea's Workers' Party, China's official Xinhua news agency said in a brief report. 

Song Tao, the head of the Chinese Communist Party Central Committee's international department, will lead the mission. 

Song had visited Pyongyang late last year to brief officials about the party's October congress. 

The festival is held in Pyongyang as part of the commemorations for the anniversary of the birth of the North's founder Kim Il Sung on April 15, 1912. 

Both North Korean and foreign artists take part, and this year's week-long event includes concerts, dance performances and acrobatics. 

China has sent art troupes to every festival since 1986, except in 2016.