Photos that have gone viral show how Macron turned part of Trump’s hand pale with a blood-squeezing grip when they met on the sidelines of the G7 summit in Canada on Friday (local time).

Another picture appears to show the 71-year-old Trump wincing slightly as he struggles to get to grips with his 40-year-old counterpart.

The relationship between the two alpha males has been something of a rollercoaster ride since they first met last year, epitomised by their infamous handshake marathon in Paris during Bastille Day celebrations last July.

Although Macron was given the honour of the first state visit of the Trump era in April, one of the most enduring images of the trip was when Trump brushed some flecks of dandruff off the Frenchman’s jacket in the White House.

The two men also traded jibes on Twitter in the build-up to the summit in Canada, which has been soured by Trump’s decision to impose tariffs on steel and aluminium exports from the European Union.

Despite their differences, the two men seem at least to enjoy a mutual respect.

“We have a very really good relationship, very special,” Trump told reporters after Friday’s handshake.

TENSE TALKS ON TRADE

US President Donald Trump has ended his trip to the G-7 summit with stern warning to foreign countries not to retaliate against US tariffs on the imports of steel and aluminium.

“If they retaliate, they’re making a mistake,” Trump warned.

The president also said that he told the Group of Seven leaders that the United States required fair access to markets and an end to unfair trade practices.

“The United States has been taken advantage of for decades and decades,” Trump told reporters, adding that he did not blame G7 leaders for the “unfair” trade deals.

The trade talks at the G7 summit were always going to be tense. America’s closest allies went into the meeting bracing themselves for a showdown with the president on the subject, as anger at being slapped with the trade tariffs by their most powerful member threatened to split the club.

On top of that, relations had already been soured by the US pullout from an international climate accord and a deal designed to contain Iran’s nuclear program.

Ahead of the meeting, the French president voiced his willingness to cut the US adrift if they could not reach some kind of consensus.

“The American President may not mind being isolated, but neither do we mind signing a six country agreement if need be,” Macron said in a tweet on Thursday.

“Because these six countries represent values, they represent an economic market which has the weight of history behind it and which is now a true international force,” he added after he had his one-to-one with Canadian president Justin Trudeau on Thursday.

Echoing Macron’s sentiments, Canadian president Justin Trudeau told reporters ahead of the summit hosted in his country that the US justification for the tariffs on national security grounds was “laughable”.

He also said Trump’s action would hurt American workers as well as Canadians.

“If I can get the president to actually realise that what he’s doing is counter-productive for his own goals as well, perhaps we can move forward in a smarter way,” Trudeau said.

This triggered a riposte from the president on Twitter.

“Please tell Prime Minister Trudeau and President Macron that they are charging the US massive tariffs and create non-monetary barriers,” Mr Trump wrote ahead of the meeting on Thursday night.

Trump then blasted Trudeau as “indignant” in another tweet.

Barely 500 days into his presidency and world leaders believe Trump has developed a knack for alienating his counterparts while pursuing his “America First” foreign policy — a pushback against a global trade system which he sees as working against US interests.