
NATO's 70th anniversary summit descended into acrimony today after comments caught on a hot mic at Buckingham Palace last night saw Donald Trump storm out and cancel his last press conference.

The US President branded Justin Trudeau 'two-faced' during a sit down with Angela Merkel this afternoon after a video emerged of the Canadian Prime Minister mocking his American counterpart at yesterday's Buckingham Palace reception hosted by the Queen.

The pair shared an awkward exchange before Trump was heard bragging about his put-down in another hot mic moment before tweeting that he would be cancelling his final press conference and flying back to Washington.

It all began when Trudeau, Boris Johnson and French President Emmanuel Macron were caught mocking Trump and his lengthy impromptu press conferences in a video filmed by Canadian TV.

The video clip shows Boris asking Macron why he was late to the event, which was attended by Prince Charles and the Duchess of Cambridge, before the Canadian and French leaders chime in.

Body language expert Judi James has examined the body language at the summit, and describes the Buckingham Palace trio as 'naughty school boys' and revealed Mr Johnson appeared keen to stay out of the gossip, while Trudeau and Macron took the lead.

The Prime Minister's 'self-diminishing rituals' as he bends his knees and shrinks down suggest he was happy to duck out and let the others take over, James tells MailOnline.

Trudeau scans everyone's faces as he leads the joke and exclaims: 'He was late because he takes a 40 minute press conference off the top'.

But after he gestures at Macron, the French President takes over 'leaning forward conspiratorially' and 'waggling one finger' as he enjoys giving his view as part of the gossiping, says James.

A tense meeting between Donald Trump and Justin Trudeau was captured on camera at the NATO summit in Watford, Hertfordshire today after Trump was questioned by reporters about Trudeau's comments caught on a hot mic yesterday Mail Online body languge expert Judi James said about this photo: 'Trudeau is a man whose body language exudes industrial-strength charm tinged with the kind of signals of modesty that would place him high on the ‘likeability’ spectrum. He appears to be leaning into Trump here and turning his head towards the President with a part-smile but Trump is looking down reflectively and his part-open mouth and slight jaw jut suggests an air of resolve and determination.'

The US leader was asked about Justin Trudeau's comments at Buckingham Palace yesterday evening during a one-on-one press conference with German Chancellor Angela Merkel at the summit today. Mail Online body language expert Judi James says about this story: 'Trump and Merkle’s poses resemble the rather frosty body language of their first press conference, when Trump refused to shake her hand and there was a feeling the tumbleweed might blow around the room at any moment. This slightly slumped pose is classic Trump when he’s posing with another world leader but with a few glaring exceptions. Trump often sits with his hands clasped between his splayed knees but here his hands are in a loose clasp rather than the downward steeple power-pose he normally uses to emphasise his alpha status. His eyes dart to the side but with a reflective look and his lips are pursed and pulled in to suggest regret or suppressed exasperation.

Trump appeared stone-faced as the leaders assembled to pose for a group photograph at the Grove Hotel in Watford. Mail Online body language expert Judi James says: 'Trump is pulled up to full height here and his rather grim facial expression and the way he’s brought one hand up in a partial hail to the cameras suggests he’s keen to re-boot his status. His brows are pulled into a frown and his lips are clamped.

Trump does not look happy as other leaders surround him smiling trying to pose for a group photograph at the summit

Ducking out: Boris Johnson's 'self-diminishing rituals' as he bends his knees and shrinks down suggest he is happy to duck out and let the other leaders take over, body language expert Judi James tells MailOnline

Telling jokes: Trudeau scans everyone's faces as he leads the joke and exclaims: 'He was late because he takes a 40 minute press conference off the top'

Orchestrating the comedy: French President Mavron takes over the conversation, 'leaning forward conspiratorially' and 'waggling one finger' as he enjoys giving his view as part of the gossiping

He and Trudeau shared an awkward exchange before Trump left the summit, with the Canadian leader beaming at him, while his US counterpart kept a very straight face.

James said of the conversation: 'Trudeau is a man whose body language exudes industrial-strength charm tinged with the kind of signals of modesty that would place him high on the 'likeability' spectrum.

'He appears to be leaning into Trump here and turning his head towards the President with a part-smile but Trump is looking down reflectively and his part-open mouth and slight jaw jut suggests an air of resolve and determination.'

In the clip from last night, the three world leaders seem to be discussing why the French President was late during the London summit, held to mark the alliance's 70th anniversary.

None of the men mention Trump by name but Trudeau seems to be referring to the US president's talks with the media throughout Tuesday.

The video shows Mr Johnson asking: 'Is that why you were late?', before Canadian Prime Minister Trudeau, swigging from his drink, shoots back: 'He was late because he takes a 40 minute press conference off the top.'

On Boris, James tells MailOnline: 'Although Boris appears to orchestrate the humour in the group, bending his knees as he speaks to suggest he's making the rest of the circle laugh, he soon appears happy to duck out and allow Trudeau and Macron to take over.'

She explains how Trudeau leads the group in giving his views on Trump's timekeeping and makes eye contact with the whole group to ensure he dominates before 'passing the baton' to Macron.

He appears to have a 'rather naughty sense of humour' in the way he leads the conversation, she adds.

Trudeau swigs from his drink and gestures towards the French President as if he is passing the baton' to Macron to give his take on the situation

The expert says: 'Trudeau is the most active here in terms of conducting the comedy, performing a one steepled brow gesture to show humour and scanning all the faces in the group as he speaks like a man telling a joke and wanting to check everyone is laughing.

'He even appears to spread the gossip by inviting Macron to join in, nudging him with one hand as though nudging his memory.

'Trudeau then rubs his nose as Macron joins in and takes over, using this announcement gesture to signal Macron can pick up the baton.'

Macron's words are inaudible as he is turned away from the camera, but he soon starts gesturing with enthusiasm.

James says: 'Macron's gossip style looks pretty pronounced here as he leans forward conspiratorially and waggling one finger as well as looking round furtively in what looks like a bid to check the subject of their conversation is not within earshot.

'While he and Trudeau appear to be in full flow and when even Princess Anne looks keen to join in, Boris's signals suggest he's enjoying the stories but that he might be more cautious about being the one telling them.'

Dutch Prime Minister Mark Rutte, who is also in the group, then appears to confirm the group are talking about Trump as he interjects with the words 'fake news media' while Macron is talking.

The French leader pats him affectionately on the arm, laughing and appearing to agree with him.

Trudeau appears to have a 'rather naughty sense of humour' in the way he leads the conversation

Later he added: 'You just watches his tram's jaws drop to the floor', although he doesn't mention Trump by name

Commenting again on Mr Johnson's unusual caution, she adds: 'Boris actually looks like the man being cautious here although he might have been the catalyst to some of the fun.

'His knee-bending and self-diminishing rituals suggest he might be placing a slightly amusing comment but its the others that then run off with it while Boris begins to scan the room rather than pitching in too hard.'

None of the men mentioned Trump by name but Trudeau seems to be referring to the US president's talks with the media throughout Tuesday.

He spoke at length to reporters in the afternoon after an awkward press conference with Emmanuel Macron, following on from an earlier and equally lengthy chat after a sit-down with NATO president Jens Stoltenberg in the morning.

Describing the moment Trump was asked about the video exchange by reporters, James said: 'Trump and Merkle's poses resemble the rather frosty body language of their first press conference, when Trump refused to shake her hand and there was a feeling the tumbleweed might blow around the room at any moment.

'This slightly slumped pose is classic Trump when he's posing with another world leader but with a few glaring exceptions.

'Trump often sits with his hands clasped between his splayed knees but here his hands are in a loose clasp rather than the downward steeple power-pose he normally uses to emphasise his alpha status.

'His eyes dart to the side but with a reflective look and his lips are pursed and pulled in to suggest regret or suppressed exasperation.'

Commenting on pictures of Trump looking stone-faced as Mr Johnson and Foreign Secretary Dominic Raab beam behind him, she added: 'Trump cuts quite a solitary figure, sitting alone and studying his documents with his eyes down and brows raised while the other leaders seem to be doing some good-humoured socialising, especially Boris and Dominic Raab, who appear to be standing behind Trump's chair to share a laugh.

'The two men are in a partial hug here and both grinning widely. Boris's left hand appears to be balled into a fist and his dimpled smile and puckered lips suggest he's feeling especially good-humoured. '