Japan has conveyed its concern to China over a Chinese national suspected of spray-painting graffiti on a stone pillar at Tokyo's Yasukuni Shrine.

The shrine honors Japan's war dead. Those remembered include leaders convicted of war crimes after World War Two.

Foreign Minister Kamikawa Yoko said in a news conference on Tuesday that the ministry conveyed its concern to the Chinese government through diplomatic channels.

The graffiti in red paint was discovered on Saturday. A video posted on Chinese social media showed a man spray-painting the pillar. Tokyo police suspect the Chinese national in the video is responsible for the graffiti and are investigating.

Kamikawa said creating and spreading a video that affirms and encourages such an act is unacceptable.

She said she called on China's government to urge the country's citizens to comply with laws and regulations and to act calmly.