Joe Biden has said President Donald Trump’s refusal to concede victory in last week’s White House election is “an embarrassment”.
But the US president-elect – who has been making contact with foreign leaders – insisted nothing would stop the transfer of power.
Mr Trump meanwhile tweeted he would ultimately win the race that all major TV networks have forecast he lost.
As happens every four years, US media projected the election victor.
None of the state-by-state results have yet been certified. Several vote counts are continuing, and the outcome will only be set in stone once the US electoral college meets on 14 December.
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The electoral college is made up of delegates from each state. They are tasked with choosing the next president according to how their state voted. Mr Biden is projected to win more than the 270 electoral college votes needed to secure the presidency.
The Democrat has a period of transition until his inauguration on 20 January to choose his team and prepare to take the reins of power.
How does Mr Biden see the transition?
The president-elect was asked by a reporter on Tuesday what he thought of President Trump’s refusal to acknowledge defeat.
“I just think it’s an embarrassment, quite frankly,” Mr Biden, a Democrat, said in Wilmington, Delaware.
“The only thing that, how can I say this tactfully, I think it will not help the president’s legacy.”
“At the end of the day, you know, it’s all going to come to fruition on January 20,” he added.
Mr Biden has been fielding phone calls with foreign leaders as he prepares to assume office.
UK Prime Minister Boris Johnson, Irish Taoiseach Micheál Martin, French President Emmanuel Macron and German Chancellor Angela Merkel were among those he spoke to on Tuesday.
Referring to those calls, Mr Biden said: “I’m letting them know that America is back. We’re going to be back in the game.”
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But as he and Vice President-elect Kamala Harris forge ahead, a little-known government agency led by a Trump appointee is stalling the handover.
The General Services Administration is tasked with co-ordinating funding and access to federal agencies for incoming administrations.
However, it has so far declined to formally recognise Mr Biden as president-elect, which means that the transition team is yet to receive $9.9m in federal funds and has not been able to send its staff to key departments.
In a statement, the GSA said its administrator “ascertains the apparent successful candidate once a winner is clear based on the process laid out in the Constitution”.
In past transitions, the GSA recognised the new president soon after victory was declared. The only exception is the disputed vote in 2000 when it waited for a Supreme Court ruling on 14 December which decided the election in favour of George W Bush.
Despite the delay, Mr Biden said: “We don’t see anything slowing us down, quite frankly.”
What do Republicans think of Mr Biden’s declaration of victory?
On Tuesday, Mr Trump took to Twitter to fire off several tweets in capital letters about “massive ballot counting abuse”, asserting: “We will win!”
His tweets were labelled by the social media network as disputed.
The president has been making claims that Mr Biden was only able to win the election through electoral corruption, but no proof has emerged so far to support the allegations.
US Secretary of State Mike Pompeo, a Trump loyalist, told a news conference at the Department of State on Tuesday that once every “legal” vote was counted a “second Trump administration” would begin.