Trump told G-7 leaders that ‘NATO is as bad as NAFTA’: report.

The report highlights what appears to be a growing rift between Trump and the United States' Western allies.

Trump announced that U.S. would slap hefty steel and aluminum tariffs on the European Union, Canada and Mexico, sparking retaliatory remarks from the U.S. trading partners. The heightened rhetoric between the leaders has injected more uncertainty into the future of NAFTA.

The president involved himself in a war of words with Canadian Prime Minister Justin Trudeau in the immediate aftermath of the G-7 summit, calling him "very dishonest & weak." Trudeau has vowed to retaliate against steel and aluminum tariffs the U.S. has put on Canada's metals industries.

Trump earlier accused Canadians of crossing the border with the U.S. to buy products and "smuggle" them back into their country because their tariffs are so high.

President Trump earlier this month reportedly told the leaders of the Group of Seven member countries that NATO was "as bad as NAFTA," according to Axios.

At the G-7 summit in Canada, Trump reportedly said the North Atlantic Treaty Organization was "too costly for the U.S" and compared it to the North American Free Trade Agreement that he has often targeted as a bad deal.

Trump made the comment after telling the G7 leaders that Crimea probably should belong to Russia because everyone there speaks Russian, the source added. Trump then went on his usual riff about Germany not paying its fair share of defense spending, said the Europeans weren't paying enough and that the U.S. is being ripped off.