Greece from Monday intends to fine all people ages 60 and over who aren't vaccinated against Covid-19 as a way to boost lagging inoculation levels and reduce pressure on health care.

Prime Minister Kyriakos Mitsotakis has told seniors the simplest way to avoid the levy is to get vaccinated.

"To the few of our fellow citizens over 60 who are still unvaccinated, I encourage them today: take the step," he said on Saturday. "It's not a matter of fine, yes the fine will be imposed, but that's the least. Protect your life, the lives of those you love and understand that the vaccine is safe."

Greek authorities say the non-vaccinated remain at high risk for hospitalization from the coronavirus. Some nine in 10 Covid-related deaths in Greece have been among people 60 and above, while seven in 10 of those hospitalized from the virus are over 60. And of those, eight in 10 are unvaccinated.

Before the compulsory shots were announced in November, some 520,000 seniors in Greece hadn't been vaccinated, according to Health Ministry data.

Since then, about 220,000 more have rolled up their sleeves. Of the remaining 300,000 individuals, some will be eligible to apply for exemptions for medical reasons.

Holdouts may be fined 100 euros ($114) a month. The penalty will be imposed by Greek tax authorities directly to those who haven't been inoculated, and the funds collected will be given to hospitals fighting the pandemic.

At this point the government has exhausted all other means of persuasion, spokesman Ioannis Oikonomou said on Thursday.

Like much of Europe, Greece has seen daily cases hit records this month due to the highly-contagious omicron variant. Covid-related deaths are running at levels similar to the peak of previous waves.

Greece is about two-thirds fully vaccinated, below the EU average.