Tens of thousands of young people skipped school across the globe on Friday to march through the streets for an international day of student protests aimed at pushing world leaders into action on climate change.

Inspired by 16-year-old Swedish activist Greta Thunberg's weekly protests, who has been nominated for the Nobel Peace Prize for her activism, the global youth climate movement has swept the globe, with students organizing strikes on every continent.

Students flooded into the streets across Europe and Asia carrying placards that read "There is no planet B", "You're destroying our future" and "If you don't act like adults, we will."

Despite three decades of warnings, carbon dioxide emissions hit record levels in 2017 and again last year.

Loading the atmosphere with greenhouse gases at current rates will eventually lead to an uninhabitable planet, scientists say.

As youngsters hit the streets in cities across the globe, nations meeting at the UN environment assembly in the Kenyan capital Nairobi announced that they had agreed to "significantly reduce" single-use plastics over the next decade.