File photo: Agencies

Europe has seen a surge of COVID-19 cases since countries began easing restrictions aimed at curbing the spread of the potentially fatal virus, the World Health Organization said Thursday.

"Last week, Europe saw an increase in weekly cases for the first time in months," the WHO's regional director for Europe Hans Kluge told reporters.

"Thirty countries have seen increases in new cumulative cases over the past two weeks. In 11 of these countries, accelerated transmission has led to very significant resurgence that if left unchecked will push health systems to the brink once again in Europe," he warned.