In accordance with international practice and China's relevant provisions on epidemic prevention, China has made relevant arrangements and provided necessary assistance and convenience for the U.S. to withdraw its diplomats and citizens from Wuhan, said Chinese Foreign Ministry spokesperson Hua Chunying on Sunday.

Since the outbreak of the novel coronavirus in Wuhan, China has informed the World Health Organization (WHO) and relevant countries of the outbreak and maintained close communication, Hua added.

The U.S. government is working to evacuate American citizens by air from Wuhan as soon as possible, The Wall Street Journal said, quoting someone familiar with the effort.

Besides the indefinite restrictions on public transport and travel, which Chinese authorities have imposed in Hubei, more provinces and municipalities are restricting the entry of cars and suspending public transportation in a bid to control the spread of the novel coronavirus. 

Meanwhile, the Chinese Center for Disease Control and Prevention (CDC) has conducted research and development of a vaccine for the novel coronavirus, an official said on Sunday, as the center has finished the process of virus isolation so far.

Wuhan is also building a new 1,000-bed hospital to treat patients infected by the new coronavirus. 

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