WASHINGTON: US President Joe Biden has started to undo some of Donald Trump’s key policies, after being sworn in.

“There is no time to waste when it comes to tackling the crises we face,” Biden tweeted as he headed to the White House after his inauguration, BBC has reported.

President Biden signed 15 executive orders, including the one to boost the federal response to the coronavirus pandemic.

He also reversed the Trump administration’s stance on immigration and climate change.

President Biden set to work at the Oval Office having been sworn in earlier on Wednesday as the 46th president of the United States.

Biden, at 78, has become America’s oldest leader ever after serving 36 years as a U.S. senator and eight as Vice President.

With this, he will take command of a deeply divided nation besides inheriting a multitude of crises.

The inaugural ceremony was taken in the Capitol surrounded by security forces reminiscent of those in a war zone; and devoid of crowds because of the threat of the coronavirus pandemic.

(With inputs from Agencies)