The World Health Organization's European branch on Thursday said 95 percent of vaccine doses so far administered worldwide were limited to 10 countries and called for a more equitable distribution.
In terms of total doses the top countries are the US, China, the UK, Israel, United Arab Emirates, Italy, Russia, Germany, Spain and Canada.
"Collectively, we simply cannot afford to leave any country, any community behind," WHO's regional director for Europe, Hans Kluge, said at an online press conference.
Kluge said the WHO was working to get the vaccine to every country but, "it needs every country capable of contributing, donating and supporting equitable access and deployment of the vaccines, to do so."
According to website Our World in Data, over 32 million doses of Covid-19 vaccines have been administered so far.
In the WHO's European Region, which comprises of 53 countries and includes Russia and several countries in Central Asia, 31 countries have launched vaccination programmes.
But despite the start of vaccination campaigns the speed of transmission observed in some countries due to new more contagious variants, especially the so-called English and South African ones, was worrying, according to Kluge.
"This is a concerning situation," he said.
In the European region, 25 countries, including Russia, have recorded cases of the strain first discovered in the UK, and dubbed "VOC 202012/01".
"So far, we understand there is no significant change to the disease this variant produces, meaning the COVID-19 is not more, nor less, severe," Kluge said.
"At the same time, we are concerned for two reasons: This variant has a higher transmission rate. Secondly is the question of what does this mean for vaccines," Kluge added.
However, Kluge also stressed that there were still reasons to be optimistic.
"2021 will be another year of the coronavirus, but this will be a more predictable year, the situation will be easier to control."