President Donald Trump has extended emergency coronavirus restrictions for the US, where his top scientist warned up to 200,000 people could die, as the Russian capital and Africa’s biggest city readied to go into lockdown on Monday.

The reassessment by Trump, who had previously said he wanted the country back to work in mid-April, came as Britain and hard-hit Italy warned measures to prevent the spread of the disease would be in place for months to come.

Covid-19 has already killed more than 34,000 people worldwide, with the number of confirmed cases exceeding 700,000.

As of Sunday, more than 3.38 billion people were asked or ordered to follow confinement measures, according to an AFP database, as the virus infects every sphere of life – wiping out millions of jobs, postponing elections and clearing the sporting calendar.

Trump warned that the US crisis, which has seen a doubling of infections in only two days, would continue to get worse.

“The modelling estimates that the peak in death rate is likely to hit in two weeks,” he said, announcing an extension of social distancing guidelines until April 30.

“Nothing would be worse than declaring victory before the victory is won.”

The president was speaking after Anthony Fauci, who leads research into infectious diseases at the National Institutes of Health, said he believed 100,000 to 200,000 Americans could die from the disease, and millions could be infected.

The US health system is groaning under the weight of new cases.

On Sunday a charity began setting up a field hospital in New York’s Central Park to help take some of the strain off the city’s overwhelmed institutions.

“There’s lots of cases here in New York and a lot of people that need help,” said Elliott Tenpenny, a doctor and team leader for Samaritan’s Purse Covid-19 Response Team.

“The hospitals all over the city are filling up and they need as much help as they can get. That’s why we’re here.”

The human consequences of a shutdown that has seen huge chunks of the US economy grind to a halt were playing out at food banks, where organisers say demand has exploded.

“Before, there were 1.2 million people in New York who needed help for food. Now, there are three times as many,” said Eric Ripert of City Harvest, a food rescue organisation.

Meanwhile, Viet Nam News, a member of Asia News Network and a media partner of The Phnom Penh Post, suspended its print edition after a member of its staff tested positive for the virus. The number of confirmed coronavirus cases in Vietnam now stands at 194. No fatalities have been recorded so far.

Europe’s situation continued to worsen. Spain logged 838 deaths in a 24-hour period, the third consecutive day it has seen a rise.

“My ICU [intensive care unit] is completely full,” said Eduardo Fernandez, a nurse at Infanta Sofia hospital in Madrid, where authorities have set up a 5,500-bed field hospital and transformed an ice rink into a morgue.

“If it is not a complete collapse, we are on the verge,” he added.

British officials said life may not return to usual for six months, with Deputy Chief Medical Officer Jenny Harries saying it would be several weeks before doctors could tell if the current lockdown had slowed the spread of the disease.

Measures would be reviewed every three weeks, “probably over the next six months” or even longer, she said.

In Italy, which has logged a third of global deaths, the government warned citizens should be ready for a lengthy lockdown that would only be lifted gradually.

“We are in a very long battle,” said government medical adviser Luca Richeldi. “Through our behaviour, we save lives.”

Yet the strains on Italian society imposed by measures that might have seemed unimaginable just weeks ago are gradually starting to show.

The starkest example came when armed police began guarding entrances to supermarkets in Sicily after reports of looting by people who could no longer afford food.

In Germany, Thomas Schaefer, the finance minister of Hesse state, was found dead near a railway track on Saturday. The Wiesbaden prosecution’s office said they believe he died by suicide.

He apparently committed suicide after becoming “deeply worried” over how to cope with the economic fallout from the coronavirus, state premier Volker Bouffier said on Sunday.

Moscow became the latest European city to tell people to stay indoors.

Citizens will only be allowed to leave their homes in a medical emergency, to travel to jobs judged essential by the authorities, and to shop for food or medicines.

However, they will be allowed to walk their dogs within a 100m radius of their homes.