France on Thursday slapped a 9pm curfew on many of its biggest cities and Londoners faced new travel restrictions as governments imposed increasingly tough measures.

New infections have surged across Europe in recent weeks as the autumn kicks in, prompting authorities to start re-imposing restrictions relaxed over the summer.

The Czech Republic, Belgium, the Netherlands, Spain, France and the UK are among the countries causing particular concern.

The head of the World Health Organisation's Europe office urged governments to be "uncompromising" in controlling the virus.

"These measures are meant to keep us all ahead of the curve and to flatten its course," Hans Kluge said while wearing a mask.

"It is therefore up to us to accept them while they are still relatively easy to follow instead of following the path of severity."

Kluge cited epidemiological models that suggested if 95 per cent of people wear masks and follow other social distancing measures, the continent could avoid about 281,000 deaths by February.

But he warned that relaxing measures could lead to a five-fold increase in deaths across Europe by January.

European countries have registered nearly 230,000 confirmed deaths from the virus - more than the nearly 217,000 reported virus deaths so far in the United States, according to figures tallied by Johns Hopkins University.

While Germany is still in comparatively good shape, alarm bells are ringing there too.

On Thursday, health authorities reported 6638 cases in 24 hours - exceeding the previous record of nearly 6300 set in late March, although testing has expanded greatly since then.

Chancellor Angela Merkel and Germany's 16 state governors agreed on Wednesday night to tighten mask-wearing rules, make bars close early and limit the number of people who can gather in areas where coronavirus infection rates are high.

But those decisions "probably won't be enough," Merkel's chief of staff, Helge Braun, told ARD television.

The UK government on Thursday moved London and a half-dozen other areas into the country's second-highest virus risk level, meaning that millions will be barred from meeting people outside their households and will be asked to minimise travel.

"I know that these restrictions are difficult for people. I hate the fact that we have to bring them in," said British Health Secretary Matt Hancock.

"But it is essential that we do bring them in both to keep people safe and to prevent greater economic damage in the future."

Kluge of the WHO said most of the spread is happening in homes, indoor spaces and communities not complying with protection measures.

"The evolving epidemic in Europe raises great concern," he said.

"But we should not hold back with relatively smaller actions in order to avoid the same very painful damaging actions we saw in the first peak."

Slovakia, Slovenia, Croatia and Bosnia also announced record daily case numbers on Thursday.

South Korea reported 110 new cases of the coronavirus on Thursday, half of them linked to a hospital in Busan.

The numbers released by the Korea Disease Control and Prevention Agency brought the country's toatl caseload to 24,988, including 439 deaths.

At least 54 infections were reported in a hospital for the elderly in the southern port city of Busan.

More than 40 others came from the densely populated Seoul metropolitan area, tied to places including hospitals, churches, schools and offices.

The steady rise in infections is a cause of concern in a country that has just lowered its distancing measures, allowing high-risk venues like nightclubs and karaoke bars to reopen and spectators to return to professional sports.

Health officials are planning to test 160,000 employees at hospitals, nursing homes and welfare centres for senior citizens in Seoul and nearby areas as part of efforts to prevent outbreaks.

Globally, more than 38.64 million people have been reported to be infected by the coronavirus and 1,093,384 have died.

Australian Associated Press