BEIJING -- More than 2,000 industrial firms will have to move out of a Beijing district as the authorities push to improve the natural environment for what will be the city's new administrative center, Tongzhou District announced Wednesday.

Industrial campuses, processing plants and stud farms are among the entities that will have to relocate, said Tongzhou District deputy head Cui Songguang.

Tongzhou district, which is about 40 minutes' drive from the center of Beijing, was designated a subsidiary administrative center for Beijing municipality last year as part of measures to tackle overcrowding in the capital.

Cui said 786 companies had already closed and production halt orders had been issued to 331 polluting plants. The district plans to remove all polluting and low-end industries by the end of next year, Cui added.

The district is also cleaning up its waterways and planting more trees. It aims to increase the greenery coverage to 51 percent by 2020, or per capita green space to 18 square meters.

Regarding air quality, the district wants to reduce PM 2.5 by 6 percent this year, to 87 micrograms.