"He's been an embarrassment to the country," Biden added. Biden's remarks came after Trump tweeted earlier Friday that he would not attend the inauguration. To all of those who have asked, I will not be going to the Inauguration on January 20th," Trump tweeted.
"He's not fit to serve," the president-elect added of Trump, who is already facing mounting calls to step down or risk impeachment, for inciting his supporters to storm the US Capitol.
"He exceeded even my worst notions about him," Biden said. "He's one of the most incompetent presidents in the history of the United States of America." Biden said Vice President Mike Pence would be welcome at his inauguration.
Who all to attend the ceremony?
Traditionally, the incoming and outgoing presidents ride to the US Capitol together on Inauguration Day for the ceremony, a visible manifestation of the smooth change of leadership.
Joe Biden will become president at noon on 20 January regardless of Trump’s plans. However, Trump's absence represents one final act of defiance of the norms and traditions of Washington that he has flouted for four years.
Even as the current US President will not be present at the ceremony former Presidents Barack Obama, George W. Bush and Bill Clinton will be there to stand witness to the rite of democracy. The only other living president, 96-year-old Jimmy Carter, who has spent the pandemic largely at home in Georgia, will not attend but has extended “best wishes" to Biden.