US president-elect Joe Biden has said “more people may die” if the Trump administration does not help ensure a smooth transfer of power.
Mr Biden also said he was hopeful Mr Trump would be “mildly more enlightened” before the incoming president’s inauguration on 20 January.
Despite mounting public pressure, the Republican’s administration has refused to initiate the traditional transition briefings for the president-elect’s team on national security and policy issues.
Mr Trump is also blocking Mr Biden’s team from being briefed on efforts to control the coronavirus pandemic and distribute prospective vaccines.
The president-elect was speaking alongside vice president-elect Kamala Harris from his makeshift headquarters in Delaware on Monday.
When asked about the Trump administration’s lack of willingness to work with his team, Mr Biden told reporters: “More people may die if we don’t co-ordinate.
“As my chief of staff would say when we handled ebola – a vaccine is important, but it’s of little use until you’re vaccinated… how do we get over 300 million Americans vaccinated, what’s the game plan?
“It’s a huge undertaking to get it done, prioritise those greatest in need… (the Trump administration) say they have this Warp Speed programme that’s not only dealt with getting vaccines, but also how to distribute this.
“If we have to wait until 20 January to start that planning it puts us behind over a month, a month and a half.”
Mr Trump seemed to acknowledge Mr Biden’s election victory for the first time on Sunday before walking back the remark and repeating false claims of widespread voter fraud.
When asked how his team would prepare to lead the country without help from Mr Trump during the transition, Mr Biden said: “Deal with every individual organisation in the country from business to labour, Republicans and Democrats, to try to pull together a serious and consistent plan so we are ready on day one… it would make it a lot easier if the president would participate… I am hopeful that the president will be mildly more enlightened before we get to 20 January.”
When asked about tweets from the president over the weekend where he insisted he had won the election, Mr Biden laughed as he said he interpreted it as “Trumpinism”.
The president-elect also said he was speaking to leaders around the world “knowing what the outcome” of the election will be.
He added Mr Trump’s insistence that he had won were “embarrassing for the country”.
Mr Biden also said he “wouldn’t hesitate” to take the Moderna or Pfizer vaccine if they were concluded to be safe.
The president-elect and Ms Harris held a virtual meeting with a collection of labour and business leaders earlier.
Mr Biden has vowed to spend trillions of dollars to reinvigorate US manufacturing, expand healthcare coverage and combat climate change, among other priorities.
But his chief priority remains controlling the coronavirus pandemic, which is surging to record levels in the US and forcing state and local leaders to implement new rounds of restrictions on local businesses.
The president-elect has so far tried to sidestep difficult questions about whether he might support a short-term national lockdown to arrest the surge of coronavirus cases.
Since his election win, Mr Biden has devoted most of his public remarks to encouraging Americans to wear masks and embrace social-distancing measures.