US makes official return to Paris climate pact

World leaders expect Washington to prove commitment to accord after four years of inaction

The US is back in the Paris climate accord, just 107 days after it left.

While Friday's return is heavily symbolic, world leaders say they expect the US to prove its seriousness after four years of being mostly absent. They are especially keen to hear an announcement from Washington in the coming months on the US's goal for cutting emissions of heat-trapping gases by 2030.