Restaurants, cinemas and schools were shutting down from New York and Los Angeles to Paris and Asian cities in a worldwide effort to combat the coronavirus pandemic, as financial markets tumbled despite emergency action by global central banks.

Germans were asked to cancel all vacations as Canada and other countries closed their borders to all visitors. In Spain, which has the second most novel coronavirus disease (Covid-19) cases in Europe after Italy, police used drones to order people to stay at home. Airlines slashed flights, shed jobs and asked governments for billions of dollars in loans and grants.

In contrast to much of the world, Mexico and Brazil still held large political rallies and the United Kingdom kept its schools open.

Global markets reeled on Monday, with US stock indexes plunging 7% as the Federal Reserve's second emergency rate cut to near zero stoked fears of a coronavirus-driven recession.

EU finance ministers were planning a coordinated economic response to the virus, which the European Commission says could push the European Union into recession.

Leaders of the G7 countries were due to hold a video conference to discuss a joint response. A White House adviser said the United States could pump $800bn more into the economy to minimise damage.

The World Health Organisation (WHO) called on all countries to ramp up their testing programmes as the best way to slow the advance of the pandemic.

"We have a simple message to all countries - test, test, test," WHO Director General Tedros Adhanom Ghebreyesus told a news conference in Geneva. "All countries should be able to test all suspected cases. They cannot fight this pandemic blindfolded."

In Italy, there were 368 new deaths from the outbreak on Sunday, a daily toll more dire than even China was reporting at the peak of the outbreak that first hit its central city Wuhan.

"Many children think it is scary," Norwegian Prime Minister Erna Solberg told a news conference dedicated to answering children's questions about the pandemic.

"It is OK to be scared when so many things happen at the same time," Solberg said.

Several countries banned mass gatherings such as sports, cultural and religious events to combat the fast-spreading respiratory disease that has infected nearly 175,000 people globally and killed more than 6,700.

Just a month ago, financial markets were hitting record highs on the assumption the outbreak would largely be contained in China. There have now been more cases and more deaths outside mainland China than inside.

US states pleaded with the Trump administration on Monday to coordinate a national response to the outbreak, saying patchwork measures enacted by state and local authorities were insufficient to confront the coast-to-coast emergency that has killed at least 71 Americans.

"This should be a reality where the United States is put on a war footing, where the federal government mobilises all the resources necessary - and it begins with testing," New York City Mayor Bill de Blasio told MSNBC.

Without a co-ordinated federal response, the states of New Jersey, New York and Connecticut, home to more than 22mn people, struck a regional agreement to shut all movie theaters, casinos and gyms. Maryland and Washington state enacted similar restrictions.

Spain and France, where cases and fatalities have begun surging at a pace just days behind that of Italy, imposed severe lockdowns over the weekend.

Middle East business and travel hubs have started closing all lounges until the end of March. Thailand plans to close schools, restaurants, movie theatres and popular cockfighting arenas.

"The worst is yet ahead for us," said Dr Anthony Fauci, the top infectious diseases expert in the United States, a warning echoed by officials in Switzerland, where 14 have died.

Italy's Prime Minister Giuseppe Conte told daily Corriere della Sera that the outbreak was still getting worse, though the governor of Lombardy, the northern region that has suffered the worst, said he saw the first signs of a slowdown.

Britain has asked manufacturers including Ford Motor Co , Honda and Rolls Royce to help make health equipment, including ventilators to cope with the outbreak, and will look at using hotels as hospitals.

The worldwide financial policy actions were reminiscent of the sweeping steps taken just over a decade ago to fight a meltdown of the global financial system, but the crisis now is forcing entire societies to effectively shut down.

The International Olympic Committee will hold talks with heads of international sports organisations today, a source close to a federation briefed on the issue said, amid doubts the Tokyo 2020 Olympics set to start on July 24 can proceed.

The Jewish faithful should avoid kissing the Western Wall, the chief rabbi of the Jerusalem holy site said.