It may be the middle of winter in the northern hemisphere, but Donald Trump’s radiant salmon-coloured suntan has not dimmed even one lumen.

The president’s curious complexion has long been a subject of intense scrutiny, chiefly among critics and comedians, with Mr Trump previously blaming his heightened facial luminosity on the glare of energy efficient lightbulbs – which he then threatened to ban.

But a new photograph of the president outside on a windy day away from any source of artificial lighting, has delivered important new evidence on the matter, revealing the full extent of his dermal colour scheme – which does not even reach the edge of his face.

Instead, the hot orange smudge around his eyes, nose and mouth appears to come to an abrupt, and conspicuously circular end, before it reaches a much paler tone blocking off his hairline and ears in a sallow halo.

The photograph in question was taken by photographer William Moon, and published on the account @photowhitehouse.

Several similar photographs were put out by wire service photographers for AP, PA and AFP among others.

Mr Trump’s variegated visage was of course noticed by many observers online, and the picture soon went viral.

“My man looks like he fell asleep while eating a lasagna,” tweeted one viewer.

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Ultimately he was declared the Republican candidate in June 2016 Getty Donald Trump celebrity president: A decade in two halves Trump took part in the TV debate against opponent Hillary Clinton on 9 October Getty Donald Trump celebrity president: A decade in two halves Trump and wife Melania vote in the presidential election on 8 November 2016 AFP/Getty Donald Trump celebrity president: A decade in two halves Hillary Clinton conceded defeat at 2:50am on 9 November and president-elect Trump swiftly delivered his victory speech to a crowd of supporters Getty Donald Trump celebrity president: A decade in two halves News coverage around the world focused on the huge political upset that Trump's victory spelled AFP/Getty Donald Trump celebrity president: A decade in two halves Trump met with president Obama to discusss transition planning on 10 November. AFP/Getty Donald Trump celebrity president: A decade in two halves Donald Trump and Nigel Farage pose in the golden elevator at Trump Tower on 12 November 2016. Farage was the first British politician to meet with Trump after the election LeaveEUOffical/Twitter Donald Trump celebrity president: A decade in two halves The inauguration of Donald Trump took place on 20 January 2017. Trump's press secretary Sean Spicer boasted that the crowd was the 'largest ever' to witness an inauguration, a claim that was proved not to be true Getty Donald Trump celebrity president: A decade in two halves In his first 100 days as leader, Trump signed 24 executve orders, the most of any president AFP/Getty Donald Trump celebrity president: A decade in two halves One of Trump's most memorable election pledges was to build a wall between the US and Mexico. 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Getty

Jenny Jones, Baroness Jones of Moulsecoomb, a Green Party politician in the UK, tweeted: “Can’t someone help him?”

“Didn’t Justin Trudeau get in trouble for that?” one person responded to the photograph, a reference to the Canadian PM's history of blackface.

Others compared the president to a “reverse Panda”.

But the apparent make-up mishap also engendered sympathy from those who have suffered the impact of fake tan streaks. It has been reported by Vanity Fair that Mr Trump does all his own make up.

A black and white version of the same image highlights the sharp contrast between Mr Trump’s face and the event horizon of his scalp.

Mr Trump’s bizarre skin tones have previously been explored in detail by critics seeking to question his health.