US President Joe Biden signed 15 executive orders, including starting the process of rejoining the Paris agreement on climate change, after being sworn into office on Wednesday.
Newly-inaugurated Biden and vice president Kamala Harris were inaugurated on Wednesday, and the new administration wasted little time afterwards, undoing a number of predecessor Donald Trump's actions.
Among the executive actions taken by Biden were to sign a document ensuring the US rejoins the Paris agreement alongside a sweeping order tackling climate change, as well as revoking the presidential permit granted to the Keystone XL oil pipeline.
We are going to combat climate change in a way that we have not done so far."
Biden also signed into law a mask mandate on federal property and for federal employees, established a new White House office to coordinate the administration's response to the coronavirus pandemic and stopped the process of the US leaving the World Health Organisation.
Biden said: "Some of the executive actions I am going to be signing today are going to help change the course of the covid crisis, we are going to combat climate change in a way that we have not done so far and advance racial equity and support other underserved communities. These are just all starting points."