A South Korean delegation dispatched by president-elect Yoon Suk-yeol met Japan's foreign minister in Tokyo on Monday, hoping to lay the groundwork for warmer ties after years of tensions.
Japan and South Korea are both democracies, market economies and US allies, but their relationship has been strained at times over historical disputes related to Tokyo's 1910-45 colonial rule of the Korean peninsula.
In recent years, the neighbours have been locked in a bitter trade and diplomatic row related to these issues including compensation for World War II sex slaves.
But North Korean missile tests and China's growing regional military capacity, as well as visits by US President Joe Biden to Seoul and Tokyo this year, appear to have put cooperation back on the agenda.
Japan's deputy chief cabinet secretary Yoshihiko Isozaki said ties with South Korea were "of paramount importance" as North Korea's "nuclear and missile development becomes more and more active".
"As the international community faces a historic crossroads, we believe fostering healthy Japan-South Korean relationships is essential to realising a rule-based international order," he said.
Local media said the seven-member delegation, which arrived on Sunday and is expected to leave on Thursday, includes policy experts including a former diplomat and professor.
It is headed by Chung Jin-suk, a lawmaker from the conservative People Power party whose leader Yoon won a presidential election last month, promising a more hawkish policy on the nuclear-armed North.
"The two countries agreed that their cooperative relationship should be closely maintained and strengthened," Chung told reporters after meeting Foreign Minister Yoshimasa Hayashi and his deputy.
But he said no specific proposals had been presented so far.
There have been reports the team will meet Prime Minister Fumio Kishida this week, but no confirmation. The delegation is believed to be carrying a letter to him from Yoon, who takes office on May 10.
"We need to further Japan-South Korea relationships based on the friendship we have built since the normalisation of our diplomatic ties in 1965," Isozaki said.
"And we have high hopes for the leadership of the next South Korean president."