A senior Chinese environmental official says air pollution readings posted by foreign embassies are an unacceptable interference in Chinese internal affairs.

The comments made Tuesday by Vice Environment Minister Wu Xiaoqing were a clear reference to the air quality readings posted regularly on the Twitter page of the U.S. Embassy in Beijing.

Wu said only the Chinese government has the authority to publish such readings. He said pollution figures posted by foreign embassies and consulates are illegal and should stop.

The U.S. embassy posts hourly air-quality data on its popular Twitter feed, which boasts over 19,000 followers. The U.S. consulate in Shanghai has a similar service.

The embassy feed was set up in 2009 following widespread complaints that official government readings were understating pollution levels in the smog-filled capital city.

In January, Beijing authorities promised to start publicizing more precise data on the city's air quality. But there are often large differences between the official and U.S. readings, which Chinese government officials have criticized as being “unscientific.”

Wu said Tuesday that air quality figures should only be released by “competent” authorities, and that the readings should be based on a large area and not single monitoring stations such as the embassy grounds. The embassy acknowledges on its website that its readings should not be used to provide city-wide pollution readings.

Wu said the standard China uses to measure its air pollution takes into account the level of its “current stage of development,” echoing the government's insistence that it should not be held to the same standards as more developed countries.

He declined to say what actions the government would take if foreign embassies did not stop publishing air quality readings.