"The pandemic will be over once we reach 70% minimum coverage in vaccination," WHO's regional director for Europe Hans Kluge told Agence France-Presse (AFP) in an interview.
Kluge also said that one of his main worries was the increased contagiousness of new variants of the coronavirus.
"We know for example that the B.1617 (Indian variant) is more transmissible than the B.117 (British variant), which already was more transmissible than the previous strain," Kluge said.
According to the Belgian doctor, speed is "of the essence" in a pandemic.
"Even when WHO declared a pandemic, many countries were still waiting, we lost valuable time."
While the regional director, who has held the position since February 2020, lauded calls for solidarity he stressed that a speedy rollout of vaccines was of the utmost importance.
"Our best friend is speed, the time is working against us, the vaccination roll-out still goes too slow," Kluge said.
"We need to accelerate, we need to enlarge the number of vaccines."
In the 53 countries and territories that make up the WHO's European region – including several in Central Asia – 26% of the population has received a first dose of a COVID-19 vaccine. In the European Union, 36.6% of the population has received at least one dose, according to a count by AFP.