For as long as anyone can remember, there has existed a 'special relationship' between the U.S. and the UK. But have we been blind to the blossoming transatlantic union that bypasses Downing Street and the White House?
As footage is released of Prince Harry and Barack Obama engaging in some light banter while the former prepared to interview the latter for the Today programme in September, here's six times the duo have proven that long-haul is no barrier for enduring friendship...
1. A meeting of minds: the Oval Office, October 2015
Prince Harry and Barack Obama first met a little over two years ago, when the latter was still in power. Beforehand, Obama commented on the prospect of the meeting; "I've had an opportunity to spend a lot of time with so many of his family members, but this is the first time that we had a chance to talk directly."
During a congenial hearth-side chat, sparks flew in the absence of an actual fire. It would be the start of a heart-warming relationship.
2. Meet the family: Kensington Palace, April 2016
Seven months after that initial meeting, Harry and Barry took the next step together: introducing each other to their respective families.
During a trip to the UK, the Obamas dined at Kensington Palace, with the Duke and Duchess of Cambridge in attendance. It was the first time that any of the young royals had entertained a head of state privately and arguably the most significant event they have hosted at Kensington Palace.
3. Just dropping in: Kensington Palace, May 2017
You know you're good buddies when you can just pop around for a good old chinwag.
Just a month after the dinner date, Barry dropped in on his old pal Harry to hang out and discuss numerous developments in their respective countries. According to the official palace Twitter account, the topics covered included: "support for veterans, mental health, conservation, empowering young people and the work of their respective foundations."
Obama also offered “condolences to the victims of the Manchester attack and support for those recovering from injuries.”
Good to see my friend Prince Harry in London to discuss the work of our foundations & offer condolences to victims of the Manchester attack. https://t.co/7azv4BV2Nt
— Barack Obama (@BarackObama) May 27, 2017
4. 'I've got a couple of tickets to the game this evening...' Invictus Games, Toronto, September 2017
Images of Harry and Barry taking in events at the former's Invictus Games bounced around the world a couple of months ago. None, however, could rival the pic captured by Hayley Stover, an 18-year-old carpentry student, who got a selfie with the two bezzies while watching USA vs France in the wheelchair basketball
Stover said afterwards: "I did hear Obama ask about Meghan and Harry just let him know she had been to watch the tennis with him. Harry was really smiling when he said it. He looked really happy, it was cute."
5. Part of the team: Invictus Games, September 2017
During the same Games, Harry and Barry posed in relaxed fashion with the members of the U.S. team at the Invictus Games in Toronto. A spokesman for Mr Obama said the former president wished to lend his support to American competitors “to once again express his gratitude for their service and his admiration for their courage and resilience.”
It was also during this meet-up that the pair recorded their Today interview, to be broadcast on December 27.
6. I'll be there for you: the Obama Foundation Summit, October 2017
The next month, the two buddies appeared in more formal circumstances, as Harry returned Barry's favour by supporting one of the former US president's work commitments – the Obama Foundation Summit, which aims to inspire a new generation of leaders.
Harry took to the stage at the summit in Chicago, discussing philanthropy, youth engagement, and the importance of giving back to society having been born into privilege.