Thousands of protesters angry at COVID-19 restrictions rallied in cities across Europe on Saturday as several nations reimposed partial lockdowns to fight new surges in infections.

The coronavirus, which has killed more than 2.7 million people, has been spreading faster recently, with the number of new infections up globally by 14 per cent in the last week, according to AFP data.

That has forced governments to impose social distancing and movement restrictions again, even as vaccines are rolled out, with residents in Poland, parts of France, and Ukraine's capital the latest to face fresh curbs.

But populations have grown increasingly weary of the economically painful restrictions, and frustrations spilled over in cities across Europe with thousands marching in Germany, Britain and Switzerland.

Demonstrators in the German city of Kassel held up signs including "End the Lockdown" and "Corona Rebels", as they participated in a protest organised by activists from both the far-left and the far-right, as well as peddlers of baseless conspiracy theories about the pandemic and vaccines.

Authorities used water cannon, batons and pepper spray to disperse the Kassel protesters, which a Kassel police spokesman said numbered between 15,000 and 20,000 — one of the largest such rallies so far this year.

Thousands also demonstrated in London against virus curbs, including many carrying signs promoting coronavirus conspiracy theories. The Metropolitan Police said 36 people were arrested, most for breaking those restrictions, with a spokesperson adding that a group of around 100 demonstrators threw missiles at officers.

There were also anti-restrictions protests in Amsterdam, Vienna, the Bulgarian capital of Sofia, and the Swiss town of Liestal.

‘We vaccinated, baby’ 

Across the Atlantic, American authorities imposed a state of emergency and a curfew on Saturday in Miami Beach, Florida, to deal with uncontrollable throngs of people partying during spring break.

This year, with approximately 13 per cent of US residents vaccinated, the atmosphere in the city is particularly festive and the illusion that the pandemic is now under control in the world’s worst-hit nation is pervasive.

"Just go get your vaccine y’all so that you could come out here and have a good time like us because we vaccinated, baby,” Jalen Rob, another student from Texas, told AFP.

Despite the vaccine rollout, health experts have stressed that people still need to remain cautious — or there may be more spikes in infections.

"I’m really concerned if we declare victory prematurely that that’s the same thing that’s going to happen,” top US expert Anthony Fauci said Saturday on NBC’s "Today” show.

"Vaccines are coming on really well... If we can just hang on a bit longer, the more people get vaccinated, the less likelihood that there is going to be a surge.”

Like many other parts of the world, US authorities are also battling vaccine scepticism and even denial, fuelled by the spread of baseless misinformation about the pandemic.

"If they [authorities] try to make me get it, they’re just going to [have to] put me in jail,” Todd Engle, 58, told AFP from the porch of his home in Martinsburg, West Virginia.

"I just don’t trust them.”

‘Unavoidable’ Olympics fan ban 

Hopes of ending the pandemic have been boosted with rollouts starting in some poorer parts of the world as well, including the Palestinian Territories, where authorities said they would start giving out shots on Sunday.

The row in Europe over the AstraZeneca jab meanwhile showed no signs of abating, with European Union chief Ursula von der Leyen threatening to halt exports of the vaccine if the bloc does not receive its deliveries first.

With more than 400 million vaccine doses already administered globally, organisers of the Tokyo Olympics had previously billed this summer’s already delayed Games as a chance to provide "proof of humanity’s triumph over the virus”.

But on Saturday, Olympics chiefs announced that overseas fans would be banned as it remains too risky to invite large international crowds to Japan.

"It was an unavoidable decision,” said Tokyo 2020 chief Seiko Hashimoto.

The unprecedented ban will make the Tokyo Games the first ever without overseas spectators.