BEIJING, Feb 7 — Chinese President Xi Jinping assured his US counterpart today that China was doing all it can to contain a new coronavirus that has killed almost 640 people, including a doctor who sounded the alarm only to be threatened by police.

China was gradually achieving results and was confident it could defeat the epidemic with no long-term consequences for economic development, Xi told President Donald Trump in a telephone call, according to state television.

The call to the White House, which China has accused of scaremongering over the epidemic, came as China's central bank vowed to step up support for the economy to cushion the blow of the outbreak.

First-quarter growth in the world's second-biggest economy could slow by 2 percentage points or more, from 6 per cent, in the last quarter, analysts say, but could rebound sharply if the outbreak peaked soon.

Chinese stocks were heading for their worst week since May while elsewhere in Asia, financial markets slipped after several days of gains.

Xi had earlier declared a "people's war” on the virus, saying China had responded with all its strength and "the most thorough and strict prevention and control measures,” state media said.

The rallying cry came amid an outpouring of grief and anger on social media over the death of ophthalmologist Li Wenliang.

Li, 34, was one of eight people reprimanded by police in the central city of Wuhan, the epicentre of the contagion, last month for spreading "illegal and false” information about the flu-like virus.

His social media messages warning of a new "SARS-like” coronavirus — a reference to Severe Acute Respiratory Syndrome (SARS) which originated in China and killed almost 800 people around the world in 2002-2003 — triggered the wrath of police.

China was accused of trying to cover up SARS. — Reuters