The unification ministry on Tuesday expressed hope for the early reopening of a now-shuttered industrial complex in North Korea's border town of Kaesong as it marks the fifth anniversary of its closure amid chilled inter-Korean relations.

South Korea closed the Kaesong Industrial Complex in February 2016 in retaliation against the North's nuclear and missile provocations. The Kaesong complex had been considered one of the most tangible symbols of inter-Korean reconciliation.

"The government has made efforts to create an environment for the reopening of the Kaesong complex but there have been difficulties to produce actual results," Lee Jong-joo, the ministry's spokesperson, said.

"The resumption of the Kaesong complex was agreed upon by the leaders of the South and the North in 2018," she said. "We hope that the day will come earlier than later that we can discuss the resumption of the operation of the Kaesong complex with inter-Korean relations being improved."

South Korean President Moon Jae-in and North Korean leader Kim Jong-un agreed during a summit in Pyongyang in September 2018 to reopen the Kaesong industrial park, along with a tour program to Mount Kumgang on the North's east coast, as soon as conditions are met.

Those projects, however, have remained stalled amid little progress in the North's denuclearization negotiations with the United States.

Cross-border ties have chilled further since North Korea blew up a joint liaison office in Kaesong last June in anger over anti-Pyongyang leaflets sent from South Korea. (Yonhap)