The foreign ministry in Tokyo yesterday proposed a meeting with Chinese officials about the choking smog over Beijing, which is now being seen in Japan.
The ministry told China "the Japanese government is concerned and is closely monitoring the recent serious air pollution in China" as it might affect Japan's environment as well as Japanese nationals in the country, a statement said.
Tokyo proposed that the countries hold talks as soon as the Lunar New Year holiday season ends this month, to discuss how the two parties can co-operate over the problem.
The suffocating smog that has blanketed swathes of China is hitting parts of Japan, sparking warnings of health risks for the young and the sick.
Relations between Tokyo and Beijing are already strained over the sovereignty of the Diaoyu Islands - known as the Senkakus in Japan.
That dispute intensified further this week after Japan alleged a Chinese warship's radar system had locked onto a Japanese destroyer.