US President Donald Trump on Sunday signed into law a $2.3 trillion pandemic aid and spending package, restoring unemployment benefits to millions of Americans and averting a federal government shutdown in a crisis of his own making.

Trump, who leaves office on Jan. 20 after losing November's election to President-elect Joe Biden, backed down from his earlier threat to block the bill, which was approved by Congress last week, after he came under intense pressure from lawmakers on both sides.