The death toll from China's coronavirus outbreak has surpassed 250, the government said Saturday, as foreign nations tightened restrictions on travellers from China in response to the rapid spread of the illness.

At least 258 people have died and more than 11,000 people have been infected in China by the new coronavirus, according to new figures from officials in hard-hit Hubei province.

A sign in various languages, including Chinese, tells customers that masks have sold out at a pharmacy in Rome
A sign in various languages, including Chinese, tells customers that masks have sold out at a pharmacy in Rome AFP / Alberto PIZZOLI

Fresh cases have been detected abroad, with more than 20 countries now affected.

The top Communist Party official in Wuhan, the central city of 11 million people where the virus first emerged in December, on Friday expressed "remorse" because local authorities acted too slowly.

AFPTV / Yan ZHAO

Last week, China's central government finally jumped into action, effectively sealing off Wuhan and surrounding Hubei province, and curbing travel across the nation of 1.4 billion people.

But the epidemic has spread far and wide as Chinese people travelled across the country and abroad over the Lunar New Year holiday that started last week.

Medical staff in protective clothing carry a suspected virus patient from an apartment in the central Chinese city of Wuhan, the epicentre of the outbreak
Medical staff in protective clothing carry a suspected virus patient from an apartment in the central Chinese city of Wuhan, the epicentre of the outbreak AFP / Hector RETAMAL

The World Health Organization has declared the outbreak a global health emergency, but said it was not recommending any international trade or travel restrictions.

Countries nonetheless intensified travel curbs.

Countries or territories with confirmed cases of the novel coronavirus
Countries or territories with confirmed cases of the novel coronavirus AFP / Patricio ARANA

The United States told its citizens not to go to China and urged those already there to leave -- drawing a sharp rebuke from Beijing, which said the move was "certainly not a gesture of goodwill."

On Friday, Washington doubled down, declaring its own public health emergency and temporarily barring entry to any foreign nationals who have travelled to China in the past two weeks.

The number of confirmed new cases of the coronavirus has grown steadily to 7,711 in China, while another 81,000 people are under observation
The number of confirmed new cases of the coronavirus has grown steadily to 7,711 in China, while another 81,000 people are under observation AFP / NICOLAS ASFOURI

Japan has joined the US, Britain, Germany and other nations that have recommended that their citizens avoid China.

Singapore's government barred arrivals from China and transit passengers who visited the country in the past 14 days.

Ambulances arrive at Haneda airport in Tokyo to meet a second charter flight carrying Japanese citizens from the Chinese city of Wuhan
Ambulances arrive at Haneda airport in Tokyo to meet a second charter flight carrying Japanese citizens from the Chinese city of Wuhan JIJI PRESS / STR

Mongolia will ban Chinese nationals and foreigners coming from the neighbouring country until March 2.

World markets tumbled Friday on the mounting concerns.

Chart showing cumulative number of people infected by the 2019 coronavirus in China and other countries, territories or areas, based on data from national authorities
Chart showing cumulative number of people infected by the 2019 coronavirus in China and other countries, territories or areas, based on data from national authorities AFP / Thomas SAINT-CRICQ
France became the latest country to evacuate some of its citizens from the locked-down city of Wuhan
France became the latest country to evacuate some of its citizens from the locked-down city of Wuhan AFP / Hector RETAMAL

The WHO's rare declaration of an emergency allows the UN health body to issue recommendations that the international community is expected to follow.

But it warned Friday that closing borders was probably ineffective in halting transmissions of the virus -- and could even accelerate its spread.

A French gendarme walks at the entrance of a holiday resort near Marseille, France, where French citizens evacuated from Wuhan, China, are expected to be put under quarantine for 14 days
A French gendarme walks at the entrance of a holiday resort near Marseille, France, where French citizens evacuated from Wuhan, China, are expected to be put under quarantine for 14 days AFP / GERARD JULIEN

China's ambassador to Geneva said his country was controlling the outbreak and insisted there was no need for "unnecessary panic".

Beyond government travel advisories, businesses and worried travellers have been taking matters into their own hands, with airlines suspending or reducing flights with China.

The virus is believed to have originated in a Wuhan market that sold wild animals. It then jumped to humans.

Wuhan officials have been criticised online for withholding information about the outbreak until the end of last year, despite knowing about the new illness weeks earlier.

"Right now I'm in a state of guilt, remorse and self-reproach," said Ma Guoqiang, the municipal Communist Party secretary for Wuhan.

"If strict control measures had been taken earlier, the result would have been better than now," he told state broadcaster CCTV.

People in China have so far directed their anger at local officials in Wuhan and Hubei, but the crisis could pose a challenge to President Xi Jinping, who has called the epidemic a "demon" that China can defeat.

Countries have scrambled to evacuate their nationals from Wuhan, with hundreds of US, Japanese, British, French and South Korean citizens evacuated so far, and more countries planning airlifts.

A flight carrying more than 300 Indian nationals left Wuhan in the early hours of Saturday for New Delhi.

About 200 US evacuees who landed in California on Wednesday have been put under a rare mandatory quarantine order for 14 days.

US carriers American, United and Delta joined other airlines suspending flights to China, following the State Department travel advisory.

Russia said it would evacuate more than 2,500 of its citizens holidaying on China's Hainan island, far from the epicentre of the outbreak, a day after sealing its remote far-eastern border.

The health crisis has also dented China's international image abroad and put Chinese nationals in difficult positions abroad, with some communities complaining of "latent racism" in Italy.

China on Friday sent charter planes to Thailand and Malaysia to bring Hubei residents back to Wuhan, citing the "practical difficulties" that they have encountered overseas.

More than 40,000 workers at a vast Chinese-controlled industrial complex in Indonesia's Sulawesi island have been quarantined, although Indonesia has not reported any cases.

The number of cases in China now far exceeds the 8,096 cases from SARS (Severe Acute Respiratory Syndrome), a similar pathogen that spread to more than two dozen countries in 2002-03 and killed nearly 800 people, mostly in China and Hong Kong.