BEIJING, June 7 (Xinhua) -- The head of the Chinese Center for Disease Control and Prevention (China CDC) informed his U.S. counterpart of COVID-19 at least as early as Jan. 4, according to a white paper published by China's State Council Information Office Sunday.

"On January 4, the head of China CDC held a telephone conversation with the director of the U.S. CDC, briefing him about the new pneumonia. The two sides agreed to keep in close contact on information sharing and cooperation on technical matters," said the white paper "Fighting COVID-19: China in Action."

The communication came a day after the health authorities in the city of Wuhan issued Information Circular on Viral Pneumonia of Unknown Cause, reporting a total of 44 cases.

From Jan. 3, on a regular basis, China began to update the World Health Organization, relevant countries, and regional organizations, as well as its own regions of Hong Kong, Macao and Taiwan, on the development of the disease, the white paper said.