BEIJING, Sept. 8 -- The Ministry of Environmental Protection said Friday it will dispatch supervisors to nine provincial regions this month to push for the fulfillment of annual water pollution control targets.

The regions, namely Liaoning, Heilongjiang, Anhui, Jiangxi, Hubei, Hunan, Guizhou, Yunnan and Ningxia, have seen relatively slow progress in implementing the Action Plan for Water Pollution Prevention and Control, according to a ministry statement.

Regions along the Yangtze River will be a focus of supervision, which will last for a month, the statement said.

More than 70 percent of the water in seven major river valleys, including the Yangtze and Yellow rivers, should have relatively good quality of between Grade I and Grade III by 2020, according to the plan.

In the first half of this year, the nation's water quality improved overall, but improvement varied among regions, with some having difficulty in meeting their annual targets, according to earlier information from the ministry.

The supervisors will focus on such areas as the elimination of "dark and odorous water" in major cities, construction of sewage disposal facilities, and pollution control at coastal ports and wharves.

If serious problems are found, local officials could be summoned for talks while local project approvals could be restricted, the ministry said.

Last year, 67.8 percent of monitored surface water areas were ranked from Grade I to Grade III, according to the ministry.

The share was slightly higher than 66 percent for 2015 and exceeded a target of 66.5 percent for 2016.