The political climate in the United States starkly differed four years ago from today.

Donald Trump, after shocking pollsters and winning the 2016 election against Hillary Clinton, was welcomed to the White House by then-President Barack Obama to start the peaceful transfer of power between the two administrations.

Included in that transition of power was then-Vice President Joe Biden meeting with Mike Pence.

“I just met with @VP-elect Pence at the @WhiteHouse to offer our support for a smooth, seamless transition of power,” Mr Biden wrote in a tweet dated 10 November, 2016. The tweet included a picture of the two politicians in the vice president’s office.

During the meeting, the pair talked about “the key duties of the Vice President, and discussed a number of specific policy portfolios that have been a critical focus for him during his time in office, including NATO and eastern Europe and expanding access to the middle class,” according to a readout of the meeting.

While the pair was meeting in the vice president’s office, Mr Obama was hosting Mr Trump in the Oval Office.

“I want to emphasize to you, Mr. President-elect, that we now are going to want to do everything we can to help you succeed -- because if you succeed, then the country succeeds,” Mr Obama said to his successor at the time.

Now, four years later, President-elect Biden has started his transition into the White House without the assistance of the sitting president.

Mr Trump has not yet conceded the election. Instead, he’s pursued claims of voter fraud in multiple battleground states that he lost. But the president has not provided substantial evidence to overturn any of the states called for Mr Biden.

Whether Mr Trump will concede and invite the incoming Biden administration to the White House ahead of 20 January remains unknown.

When asked by reporters on Tuesday about the transition process, Mr Biden said: “We don’t see anything slowing this down, quite frankly.”  

He added that it was an “embarrassment” that Mr Trump refuses to acknowledge the results of the 2020 election.

“It will not help the president’s legacy,” Mr Biden said.