The Chinese government warned foreign embassies against monitoring and reporting on the country's air quality.

Alluding to the U.S. Embassy's air quality reports in the country, particularly in smog-veiled Beijing, a Chinese environment official said issuing such data is technically inaccurate and goes against international conventions and Chinese laws.

"Some foreign embassies and consulates in China are monitoring air quality and publishing the results themselves," Vice Minister of Environmental Protection Wu Xiaoqing said Tuesday in a report by the state-run Xinhua news agency.

Since 2008 the U.S. Embassy in Beijing has made public the city's air quality readings based on measurements of PM2.5 -- air pollution particles less than 2.5 micrometers in diameter - which pose health risks. Those results are published hourly via the embassy's @BeijingAir Twitter account.

Last June the U.S. consulate in the southern city of Guangzhou launched @GuangzhouAir for PM2.5 readings for that city followed by the consulate in Shanghai's launch last month of @GuangzhouAir.

While Twitter has been blocked in China since 2009, users are accessing the data through third-party mobile apps.

"It is not in accordance with the Vienna Convention on Diplomatic Relations and Vienna Convention on Consular Relations and it is also against relevant environmental protection regulations," Wu said.

"According to international conventions, diplomats are obligated to respect and abide by the laws and regulations in the receiving states. In addition, they cannot interfere with the domestic issues of receiving states," he said.

Richard L. Buangan, spokesman for the U.S. Embassy was quoted by The New York Times as saying that the monitoring "is a resource for the health of the consulate community, but is also available through our Twitter feed for American citizens who may find the data useful."

"We caution, however, that citywide analysis of air quality cannot be done using readings from a single machine," he said.

Buangan declined to comment to the Times on the Vienna conventions and how it might possibly relate to the air monitors or the release of the data.

In February, China, the world's top emitter of greenhouse gases, said that it planned to include PM2.5 readings in its air quality standards and that monitoring of the smaller particles would be expanded to cities at the prefecture level or above by 2015.

Wu said Tuesday that China's 74 major cities will publish more detailed air quality data, including the PM2.5 reading, beginning the second half of this year.