"It is all too easy for extremist groups to exploit the anger and despair, and the risk of radicalization climbs," the UN chief said in a statement.

"We can already see such groups taking advantage of the COVID-19 lockdowns, intensifying their efforts on social media to spread hatred and to recruit young people who may be spending more time at home and on line," he said.

He said: "Yet, despite these hurdles and despite these risks, young people are still finding ways to engage, support each other, and to demand and drive change. We see it in our battle against COVID-19."

He said the world cannot afford a lost generation of youth.

"The world cannot afford a lost generation of youth, their lives set back by COVID-19 and their voices stifled by a lack of participation," he said.