Major courier companies in China announced on Tuesday that they will have zero tolerance for trading in illegal wildlife and wildlife products.

Representatives of 17 courier enterprises, including China Post, SF Express and STO Express, signed a proposal in Beijing on the second World Wildlife Day, promising to refuse to handle orders of illegal wildlife and wildlife products, including ivory, rhino horn and tiger bone.

"We will ensure that our employees are more informed about endangered wildlife and related products. We will also enforce stricter checks before packing the goods, and report to authorities people we find transporting such goods without permission," the enterprises said.

The proposal was signed at the suggestion of the State Forestry Administration to curb the increasing illegal trade of wildlife and wildlife products through e-commerce websites and courier companies.

"We are calling on e-commerce websites and courier enterprises to refuse to provide a platform or channel for illegal wildlife advertisements or trade," said Liu Dongsheng, deputy director of the administration.

Zhang Libao, an official of the administration, said most of the illegal wildlife trade is conducted through couriers, as e-commerce has rapidly developed in recent years.

TRAFFIC, an international organization that monitors wildlife trade, found thousands of advertisements for illegal wildlife products on websites at the end of 2014.

To avoid clampdowns, online vendors used key words like "African materials" and "white plastic" instead of ivory, said TRAFFIC, which did not disclose the websites it monitored.

TRAFFIC found around 1,500 new advertisements for these items every month since July 2012, it said in a recent report.

Zhang said he sincerely hoped that courier enterprises keep their promise and do not assist the illegal online trade of wildlife or its products.

"Otherwise the administration will take further action against the enterprises," Zhang said.

Li Yongshun, assistant president of STO Express, said cases of illegally transporting wildlife products did happen in the past because some plant products, for example, were disguised as Chinese medicine.

"We will train our staff members more frequently, inform them of endangered wildlife and wildlife products, urge them to enforce stricter checks of the goods before packing, and refuse the order if permission or qualification is absent," he said.

"We do it not only for the sake of the wildlife and the environment, but also for the reputation of our company," Li added.

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