Shigeru Ishiba, the newly elected leader of Japan's ruling party, the Liberal Democratic Party enters the venue of a press conference after the LDP leadership election, in Tokyo, Japan Sept. 27. (Reuters)

South Korea on Friday pledged to continue its cooperation with Japan's incoming government in order to maintain "positive momentum," following the ruling party's election of former Defense Minister Shigeru Ishiba as leader, setting him up to become the country's new prime minister.

"We will continue to work closely with the new Japanese cabinet to ensure the positive flow of South Korea-Japan relations," said a senior presidential official, who spoke on the condition of anonymity.

The official emphasized that Japan is South Korea's closest neighbor and partner, sharing common interests rooted in freedom, human rights and the rule of law.

A South Korean foreign ministry official also voiced optimism, noting that both countries will maintain open channels of communication to uphold the "positive bilateral momentum."

Ishiba, known for his dovish stance on historical issues between the two nations, is set to become prime minister next week, as the Liberal Democratic Party's ruling coalition holds a majority in the Japanese parliament.

Ishiba defeated Economic Security Minister Sanae Takaichi, a conservative candidate who was vying to become Japan's first female prime minister.