French President Emmanuel Macron and Canadian Prime Minister Justin Trudeau meet in Ottawa on Wednesday to form a united front ahead of a G7 summit in Quebec, where Donald Trumps aggressive trade policies are sure to raise hackles.

The two progressive forty-something leaders are scheduled to hold formal talks and a private dinner on Wednesday, followed by a joint news conference early Thursday.

Their discussions are likely to focus on Trump's decision last week to impose punishing tariffs on imports of steel and aluminum from Washington's closest allies, including Canada, the European Union and Japan.

In retaliation, all of them have either hit back with their own tariffs on US goods or threatened to do so, as well as challenging the US trade measure at the World Trade Organization.

Both Trudeau and Macron tried to persuade Trump not to impose the tariffs, to no avail.

Great disappointment

The EU and Canada were originally shielded from the aluminum and steel tariffs, but Trump put an end to that exemption last week.

Since then, Trudeau, Macron and other European leaders have toughened their tone, lamenting what they see as rising US protectionism.

Macron -- who had formed an unlikely bond with Trump -- declined to characterize his last conversation with the US leader, but unnamed White House insiders told US media it was "terrible."

Still, the French leader pledged to have a "productive and frank discussion with President Trump at the G7."

"It does not detract from the friendship we have for each other and the friendship between our two countries," he said.

Trudeau, who has been cordial with Trump, said in March he had received assurances that Canada would be spared as they worked toward a revamp of a 1994 continental trade pact with the United States.

But that all changed with the announcement of the US levies, and Trudeau retaliated with Can$16.6 billion (US$12.9 billion) in tariffs on US goods.

The two sides are also deadlocked on the negotiations over the future of their North American Free Trade Agreement (NAFTA) with Mexico, with Ottawa refusing to grant US demands for a sunset clause.

Canada has also rejected "for now" a proposal floated by the White House for new separate US trade deals with Canada and Mexico.

The left-leaning Trudeau and Macron see each other as natural allies in a world increasingly shaped by right-wing nationalism. That bond -- called a "bromance" by some analysts -- should only grow deeper ahead of the G7 in Quebec.

'G6 + 1'

The Group of Seven summit on Friday and Saturday in La Malbaie, a small town 140 kilometers (87 miles) from Quebec City, will bring together the leaders of Britain, Canada, France, Germany, Italy, Japan and the United States.

Trudeau hopes to put the focus on jobs, security concerns, cleaning up the world's oceans and empowering women. But officials concede the agenda is likely to be overtaken by trade disputes.

"I think it's fair to expect that any discussions on the global economy... in the current environment will quickly turn into a discussion about trade," a senior Canadian official told a briefing.

The other six members of the G7 are holding out hope they can find common ground with Trump, but are prepared to stand up to US protectionism.

"The challenge is to try to preserve a form of unity within the G7, but not hesitate to express firmly and strongly the interests of France and of Europe," Macron's office said.

It is not even clear if the leaders will agree on a final statement.

At the last G7 summit in Taormina, Trump refused to sign the final joint declaration, shortly after withdrawing the United States from the global Paris climate accord.

Last week's meeting of G7 finance ministers meeting in Whistler ended with six members scolding Washington over its tariffs in what French Finance Minister Bruno Le Maire described as the rise of the "G6+1."

Trudeau's office told AFP that he and Macron hoped to "strengthen multilateralism and advance progressive trade," adding: "We cannot presume the final results of the G7, but we seek to reach consensus."