KUNMING, June 28 (Xinhua) -- China-Vietnam special service windows for agricultural products were officially launched Friday, said commerce authorities in southwest China's Yunnan Province.

The special service windows, which can improve the customs clearance efficiency for the products, were set up between Hekou, a border county in the province, and Lao Cai, a port in Vietnam.

The windows made Vietnam the fifth country that opened the special service windows with China after Kazakhstan, Kyrgyzstan, Tajikistan and Mongolia.

China and Vietnam began the trial operation of the special service windows on Dec. 28, 2018. The port of Hekou imported 83,000 tonnes of cassava chips worth 79.98 million yuan (11.65 million U.S. dollars) from January to May, up 73.6 percent year on year.