The memorandum is the latest in a series of moves aimed at encouraging international environmental cooperation.

Meeting at the 15th Tripartite Environment Ministers Meeting, held in Japan in May, environment ministers from China, South Korea and Japan agreed to establish a policy dialogue mechanism on the issue of airborne pollution.

Under the mechanism, the three countries will cooperate on policies and techniques to prevent and control airborne pollution, including the development of monitoring techniques and capacity building.

The agreement underlines the already close working relationship enjoyed by the three countries in research on ozone pollution and sandstorm control, according to information provided by China's Environmental Protection Ministry.

In April, Chinese Environment Protection Minister Zhou Shengxian and France's then-minister of ecology, sustainable development and energy Delphine Batho signed an environmental cooperation agreement in Beijing, witnessed by President Xi Jinping and visiting French President Francois Hollande. Among the major areas of agreement were cooperation on improving air quality, including exchanges among environmental experts, as well as joint training sessions and symposiums.

Chai Fahe, deputy director of the Chinese Research Academy of Environmental Sciences.

He said previous cooperation had mainly focused on fields such as acid rain and sand storms, whereas now the major issues are shifting to basic research studies of key airborne pollutants such as fine particles and the development of relevant monitoring techniques.