President Moon Jae-in and former German Chancellor Gerhard Schroeder agreed that Tokyo must show sincere regret over its past.
The call followed Schroeder's visit this week to a shelter for Japan's wartime sexual slavery victims.
Visiting the top office on Tuesday, the former chancellor expressed his regret over Tokyo's reluctance to apologize to the elderly women.
President Moon noted how Germany had understood the issues of its past through sincere regret and was able to move toward the future through reconciliation and cooperation with its neighbors.
Schroeder agreed that facing up to the past lays the groundwork for sincere bilateral ties and that the current generation in Japan should certainly feel regret and responsibility about the past.