Greece makes vaccines mandatory for people 60 or older, with fines for not complying.

In a bid to bolster vaccinations among older people, the prime minister of Greece announced on Tuesday that Covid shots would be obligatory for people ages 60 or older, and that those who failed to book a first shot by Jan. 16 would face fines.

Τhe move came as the Greek health authorities try to curb a spike in coronavirus cases and deaths, while bracing for the possible effect of the Omicron variant.

About 500,000 people in Greece ages 60 or older have yet to be vaccinated against Covid-19, Prime Minister Kyriakos Mitsotakis told a cabinet meeting. Those who fail to meet the deadline will face a monthly fine of 100 euros ($113), the revenue from which will go toward funding state hospitals that have been stretched by the pandemic, he said.

Describing the policy as “an act of justice for the vaccinated,” Mr. Mitsotakis said he had worried about penalizing people but hoped they would see the move as an act of “encouragement, not repression.”

He said: “I felt a duty to stand by the most vulnerable, even if it might temporarily displease them.”

Greece is averaging more than 6,400 new cases a day, among the highest numbers since the start of the pandemic, according to the Center for Systems Science and Engineering at Johns Hopkins University. With concerns that the winter holidays will lead to the further spread of the virus, Mr. Mitsotakis said that more free testing kits would be made available over the next two months.

More than 60 percent of Greece’s population is fully vaccinated. This month, Greece barred unvaccinated people from cinemas, theaters, museums and gymnasiums, joining a growing number of European nations imposing new restrictions on those who have not had Covid shots.

Austria announced this month that vaccines would become mandatory for all adults starting in February, the first Western democracy to take such a step.

The spread of the Omicron variant has unnerved the Greek authorities, who last week barred travelers from nine African countries after researchers in southern Africa announced that a new variant had been detected. Five Greek citizens returning from Africa were placed in quarantine on Saturday even after testing negative for the virus.

The European Union’s public health body said it had confirmed 42 cases of the variant across the bloc, all of which were mild or asymptomatic.

The origins of the variant, and the threat it poses, remain uncertain.