Backed by U.S. engagement, Japan and South Korea appear to have started initiatives to, in Washington's words, "put history behind them and move the relationship forward" in the face of an increasingly assertive China and North Korea's nuclear weapons and missile development.

After U.S. Secretary of State John Kerry met South Korean President Park Geun-hye in Seoul on Thursday and called for improved ties between Washington's two key allies in Asia, hopefully before President Barack Obama visits Tokyo and Seoul in April, a senior Foreign Ministry official said, "setting aside the issue of a time limit, we would like to start a process to improve relations with South Korea."

Underlining the comment, it was learned that Junichi Ihara, director general of the ministry's Asian and Oceanian Affairs Bureau, will travel to Seoul on Tuesday and plans to meet with Lee Sang-deok, director general of the Northeast Asian Affairs Bureau of South Korea's Foreign Ministry, to seek ways to mend ties.