Japan has made its annual contribution to UNESCO after withholding the funds over the U.N. heritage body's decision to include "Documents of Nanjing Massacre" in its Memory of the World program, Foreign Minister Fumio Kishida said Thursday, citing UNESCO reforms as the reason for the change of heart.

The bitter legacy of Japan's savage military aggression before and during World War II is still straining Sino-Japanese ties more than 70 years after the end of the conflict. UNESCO last year decided to include the Chinese dossier on the 1937 massacre as part of an installment for Memory of the World, a program intended to preserve important historical materials.

Japan questioned the authenticity of the massacre documents and called for improvements in the "fairness and transparency" of the Memory of the World program to avoid it being used for political purposes.