Donald Trump has reversed his decision for White House officials to receive the vaccine in the coming days, as the roll-out begins elsewhere in the US.

Officials had previously said that senior members of the Trump administration were among the first in line scheduled to receive the Pfizer/BioNTech vaccine, however that decision has now been reversed by Trump who says White House staff should receive the vaccine "somewhat later... unless specifically necessary."

"I have asked that this adjustment be made", the president added.

It is unclear why the decision for early vaccination has been reversed. 

Mr Trump also confirmed that he was "not scheduled" to receive the vaccine, but would "look forward to doing so at the appropriate time."

Meanwhile, the vaccine has begun to be rolled out elsewhere in the US, with the first three million doses being distributed in all 50 states. 

The Pfizer/BioNTech vaccine, which boast 95 per cent efficacy, received emergency-use authorisation from the US Food and Drug Administration on Friday - with health workers and nursing home residents earmarked to be among the first to be immunised. 

President Donald Trump said late on Friday that Pfizer had “passed the gold standard of safety” in a video statement hailing the vaccine as “one of the greatest scientific accomplishments in history”.

He added: "Today our nation has achieved a medical miracle.

"We have delivered a safe and effective vaccine in just nine months."

In the first shipments, some three million doses of the vaccine are expected, with a similar amount is said to be held in reserve for the second doses.