Earth Day summit with 40 world leaders

Joe Biden marks Earth Day by hosting a two-day virtual climate summit to announce new carbon emission targets. The US President aims to kick-start a crucial year of action on climate change as he hosts 40 world leaders at an Earth Day summit. The US will commit to halving its greenhouse gas emissions by 2030, Joe Biden is set to announce. China's President Xi Jinping made a late announcement that he would attend after a jointly released US-China statement pledged increased co-operation in the fight against climate change.