He sleeps for just five hours, needs neither tea nor coffee as he works on his briefing papers, and sustains himself with nothing more than seven salted almonds.

This, at least, is the nocturnal portrait as suggested by one US newspaper, which said Barack Obama considers himself a “night guy” and has come to love the four of five late evening hours he carves out for himself whenever he is in the White House.

“Everybody carves out their time to get their thoughts together. There is no doubt that window is his window,” Rahm Emanuel, Mr Obama’s first chief of staff told the New York Times. “You can’t block out a half-hour and try to do it during the day. It’s too much incoming. That’s the place where it can all be put aside and you can focus.”

A newspaper article claims that every day the American leader reads 10 letters sent in by ordinary citizens (AP)

The portrait of Mr Obama as he approaches the final six months of his presidency is nothing less than flattering. (It may be, of course, that in truth Mr Obama likes nothing more than binge-watching episodes of The Bachelortte, while sitting with a bowl of Cheetos.)

But the picture in the New York Times details a routine in which he finds time for dinner with his family, reads 10 letters every day sent in by ordinary Americans, insists on going through all the briefing papers handed to him, and even then finds time for an occasional game of Words With Friends, a Scrabble-like online pastime.

All of this is done from the vantage point of a leather swivel chair in the White House Treaty Room, named for the many historical documents that have been signed in it, with a sports channel switched on, but the sound turned down.

The US President is apparently hands-off with senior staff, only sending occasional emails (AP)

If this is true, his ascetic, diligent regime is very different to that of his recent predecessors. George W Bush boasted that he was always in bed by 10pm, having exhausted himself with an increasingly harsh fitness regime during the day and a presidency that went off the rails.

Bill Clinton was another late nighter. But Mr Clinton’s free-wheeling nights were spent ordering pizzas, brain-storming with staff and phoning political leaders both in the US and around the world. The report suggests Mr Clinton’s aides often had to go through the White House call log the following morning, just to ascertain who he had called.

Obama in Canadian Parliament

None of that for Mr Obama, whose intrusions on senior staff appear to be no more than the occasional email informing them that he has read a document they wanted him to read, or else taken several hours to redraft by hand, a speech he is set to make. He does so sitting beneath a portrait of President Ulysses S Grant.

Obama in Cuba Show all 6 1 /6 Obama in Cuba Obama in Cuba U.S. President Barack Obama makes a face towards a group of children in the audience as he stand on stage with first lady Michelle Obama as he is introduced by Ambassador Jeffrey DeLaurentis Charge d'Affaires to the U.S. Embassy in Cuba Obama in Cuba President Barack Obama shakes hands with Cuba's Foreign Minister Bruno Rodriguez upon arrival to the airport in Havana, Cuba Obama in Cuba U.S. President Barack Obama and his wife Michelle approach Cuba's foreign minister Bruno Rodriguez as they arrive at Havana's international airport Obama in Cuba US President Barack Obama waves after his arrival on Jose Marti Airport in Havana, Cuba Obama in Cuba US President Barack Obama carries an umbrella as he is followed by First Lady Michelle Obama after their arrival on Jose Marti Airport in Havana, Cuba Obama in Cuba The 'Air Force One' jet carrying US President Barack Obama touches down at the Jose Marti Airport in Havana, Cuba

And all of this is done without the need for a boost from caffeine or even the refreshment of a soda. Most evenings, the monk-like Mr Obama sits with nothing more than a bottle of water, the report claims.

The only sustenance he allows is a handful of nuts. Sam Kass, Mr Obama’s former personal chef, said the president was very specific when it came to how many nuts he wanted to eat each night.