The World Health Organisation (WHO) has warned that nearly a quarter of million people in Europe could die from coronavirus by December amid declining vaccine uptake in the region.
Health chiefs expect there could be an additional 236,000 deaths from Covid-related illnesses by December 1.
WHO Europe director Hans Kluge expressed concern over stagnating vaccination numbers across the continent and low uptake in poorer countries.
Of the Europe's 53 member states, 33 have registered an incidence rate greater than 10 per cent in the past two weeks, Mr Kluge told journalists.
"Last week, there was an 11 per cent increase in the number of deaths in the region – one reliable projection is expecting 236,000 deaths in Europe, by December 1," Mr Kluge said.
While around half of people in Europe are fully vaccinated, vaccination numbers in the region has slowed, he said.
"In the past six weeks, it has fallen by 14 per cent, influenced by a lack of access to vaccines in some countries and a lack of vaccine acceptance in others."
Only six per cent of people in lower and lower-middle income countries in Europe are fully vaccinated, and some countries have only managed to vaccinate one in 10 health professionals.
"The stagnation in vaccine uptake in our region is of serious concern," Mr Kluge said, urging countries to "increase production, share doses, and improve access".
He said third-dose booster shot of the Covid-19 vaccination is a way to keep the most vulnerable safe and "not a luxury".
The WHO said this month data did not indicate a need for booster shots, while topping up already fully vaccinated people would further increase vaccine inequity between rich and lower-income countries.
"A third dose of vaccine is not a luxury booster [that is] taken away from someone who is still waiting for a first jab. It's basically a way to keep the most vulnerable safe," Mr Kluge said.
"We have to be a little bit careful with the booster shot, because there is not yet enough evidence," he said.
"But more and more studies show that a third dose keeps vulnerable people safe, and this is done by more and more countries in our region."
Mr Kluge urged European countries with excess vaccines to share them with other countries, particularly those in Eastern Europe and Africa.
Europe has suffered 1.3 million Covid-19 deaths since the start of the pandemic and reported more than 50 million cases. Russia has the highest toll with more than 180,000 fatalities, followed by the UK and Italy.