The bombing in Manchester struck a chord among leaders, including French President Emmanuel Macron who drew on his own country's experience of several jihadist attacks that have killed more than 230 people since 2015.
Mr Macron told the Journal du Dimanche newspaper his approach to the encounter had been about getting respect.
Weighing in on the tense exchange between the two world leaders, body language expert and retired Federal Bureau of Investigation counterintelligence and counterterrorism operative Joe Navarro said that President Trump's behavior may indicate he does not understand the meaning of a handshake - particularly when meeting other political leaders.
Macron's office has confirmed his comments, the Guardian reports.
He tends to make them fairly prolonged and uses a weird technique of gripping his counterpart's hand and giving it a yank before releasing their hand, but other world leaders seem to have caught on. "You can see Macron trying to get away from the situation - he puts his arms on Trump to stop him pulling him inwards".More news: Chelsea striker to seal move to Newcastle United this weekend
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The handshake between Macron and Trump on Thursday drew attention for its visible intensity, with both pairs of knuckles turning white from pressure.
Macron confirmed that the long handshake was a deliberate power move of his own created to show Trump he wasn't gonna let him get away with those weird bullying tactics. "It was quite a handshake, two alphas".
Or from Japanese Prime Minister Shinzo Abe, who was caught in a long, rigorous handshake.
The Washington Post's Jonathan Capehart recounted an anecdote earlier today, in which he and another, unnamed person warned France's ambassador to the United States, Gérard Araud, about Trump's beloved pump-and-pull during a party earlier this week. This is the first time the two leaders are meeting, they'll dine on tomatoes and buffalo mozzarella, veal filet with potatoes, tri-colored vegetables, and a duo of Belgian chocolate mousse.
Cameras also caught Macron swerving to avoid greeting Trump (favoring German Chancellor Angela Merkel instead) after walking up toward North Atlantic Treaty Organisation leaders Thursday at the start of the summit in Brussels.