The spread of a deadly new virus is accelerating, Chinese President Xi Jinping warned, after holding a special government meeting on the Lunar New Year public holiday.
The country is facing a "grave situation" Mr Xi told senior officials.
The coronavirus has killed at least 56 people and infected almost 2,000 since its discovery in the city of Wuhan.
The US has announced that staff at the Wuhan consulate will be evacuated on a special flight on Tuesday.
The State Department said that private Americans most at risk will also be able to board the flight to San Francisco.
Meanwhile, UK-based researchers have warned of a real possibility that China will not be able to contain the virus.
Travel restrictions have come in place in several affected cities. From Sunday, private vehicles will be banned from central districts of Wuhan, the source of the outbreak.
A second emergency hospital is to be built there within weeks to handle 1,300 new patients, and will be finished in half a month, state newspaper the People's Daily said. It is the second such rapid construction project: work on another 1,000-bed hospital has already begun.
Specialist military medical teams have also been flown into Hubei province, where Wuhan is located.
The urgency reflects concern both within China and elsewhere about the virus which first appeared in December.