Japan monitors the Hong Kong situation with 'deep concern'," Reuters reported referring to PM Shinzo Abe.

The PM highlighted the importance of steps that support the principle of "one nation, two systems".

“Hong Kong is an extremely important partner in terms of both tight economic ties and human relations, and it is important that the original system of ‘one nation, two systems’ be upheld and things proceed stably and democratically,” he said.

Japan expressed concern about Beijing’s move in a statement on May 28, the day China passed the law.