Be very careful, see you soon.

Republican President Donald Trump finally flew out of Washington Wednesday, skipping Joe Biden's swearing in as the 46th president of the United States, with the Democrat assuming the helm of a country beset by deep political divides and battered by the raging coronavirus pandemic.

"Unbelievable things may happen, be very careful," he said in his departure speech, adding: "Have a good life, see you soon." Biden, 78, will become the oldest US president in history at a scaled-back ceremony in Washington that has been largely stripped of its usual pomp and circumstance, due both to the coronavirus as well as security concerns following the Jan.

6 assault on the US Capitol by Trump supporters.

Trump left the White House for the final time just after 8 am (1300 GMT) by helicopter on his way to a sendoff event at Joint Air Force Base Andrews, although top Republicans, including Vice President Mike Pence, were not expected to see him off.

The president's refusal to greet his successor before attending the inauguration represents a break with more than a century and a half of political tradition, seen as a way to affirm the peaceful transfer of power.

With only a small number of attendees present, Biden will take the oath of office before US Chief Justice John Roberts just after noon (1700 GMT), placing his hand on an heirloom Bible that has been in the Biden family for more than a century.

His running mate, Kamala Harris, the daughter of immigrants from Jamaica and India, will become the first Black person, first woman and first Asian American to serve as vice president after she is sworn in by US Supreme Court Justice Sonia Sotomayor, the court's first Latina member.

The ceremony will unfold in front of a heavily fortified US Capitol, where a mob of Trump supporters stormed the building two weeks ago, enraged by his false claims that November's election was stolen with millions of fraudulent votes.

The violence prompted the Democratic- controlled US House of Representatives to impeach Trump last week for an unprecedented second time.

Thousands of National Guard troops were called into the city after the siege, which left five people dead and briefly forced lawmakers into hiding.

Instead of a throng of supporters, the National Mall will be covered by nearly 200,000 flags and 56 pillars of light meant to represent people from US states and territories.

Biden, who has vowed to "restore the soul of America," will call for American unity at a time of...