BEIJING -- China has made environmental protection and restoration a top priority in its development plan for the Yangtze River economic belt, a senior official said Sunday while discussing the national plan to boost the economy along China's longest river.

The development of the economic belt will follow a green path, with the strictest environmental protection and water resources management measures, according to an official with the leading group of the Yangtze River economic belt development.

The official said China aimed to markedly improve the environment of the economic belt by 2020, with over 75 percent of the region's water meeting Grade III standard or above and forest coverage reaching 43 percent.

China classifies water quality into six levels, from level I, which is suitable for drinking after minimal treatment, to level VI, which is severely contaminated.

By 2030, the region's aquatic environment and ecosystem will be much improved, the official said.

Environmental protection and green development are "of paramount importance" in the development of the economic belt, and the program should not be used as an excuse for unfettered construction, said the official.

Revered as the nation's "Mother River," the Yangtze traverses eastern, central and western China and joins the prospering coastal regions with the less developed inland. It is one of the busiest inland rivers for freight traffic worldwide.

China made it a national strategy to develop the Yangtze River economic belt in 2014. The move is expected to boost concerted development in riverside regions and provide new growth stimuli for China's slowing economy.

The Yangtze River Economic Belt involves nine provinces and two municipalities that cover roughly one fifth of China's land, accommodate a population of 600 million and generates more than 40 percent of the country's GDP.

The economic belt boasts huge potential but its development has been constrained by grim environmental conditions, clogged river traffic, regional imbalances and outdated industries, the official said.