QUEBEC (Canada) • The other leaders of the Group of Seven (G-7) countries must not be afraid to reach agreements without US President Donald Trump at their upcoming summit, French President Emmanuel Macron has said, as a trade war between Washington and its allies looms.

Mr Macron threatened to exclude the United States from the joint statement issued every year at the end of the G-7 summit, as part of an international pushback against Mr Trump's efforts to change trade rules.

In a tweet, Mr Macron wrote: "The American President may not mind being isolated, but neither do we mind signing a six-country agreement if need be.

"Because these six represent values, represent an economic market and, more than anything, represent a real force at the international level today."

Mr Macron is scheduled to meet one-on-one with Mr Trump during the G-7, and the Twitter barbs could be a prelude for an awkward confrontation.

Mr Macron began his trip to Canada by visiting Prime Minister Justin Trudeau in Ottawa, and emerged with a warning for Mr Trump: "None of us is eternal.

"There will be no world hegemony if we know how to organise ourselves. And we don't want there to be one."

Mr Macron said, with Mr Trudeau at his side: "The G-7 is an opportunity for us to get together and have frank, open discussions among nations who have long been allies and friends.

"There will be subjects on which the (US) President is not totally in sync with the others.

"I am thinking, of course, of climate change and trade."

The French leader added: "Our common goal is to try to find a text that can be signed by everyone...

"That said, I agree with what Justin Trudeau has said many times - the desire to sign a common G-7 declaration must not outweigh the need to be mindful of the content."

He said the Europeans and the Japanese "are not ready to give up everything" to get Mr Trump's signature, adding that it would be a "mistake".

AGENCE FRANCE-PRESSE, BLOOMBERG, WASHINGTON POST, REUTERS