(CNN) Sen. John McCain pushed back Saturday night against President Donald Trump's reversal of an agreement to sign onto a statement by the G7 countries, saying that Americans would continue to stand with its historical allies.

"To our allies: bipartisan majorities of Americans remain pro-free trade, pro-globalization & supportive of alliances based on 70 years of shared values," the Arizona senator tweeted . "Americans stand with you, even if our president doesn't."

Earlier in the evening, Trump tweeted that Canadian prime minster Justin Trudeau was "meek" and "mild" and that his statements were " false ."

Shortly after Trudeau said in an afternoon news conference that he was "happy to announce that we have released a joint communique by all seven countries" indicating that the US had signed on, Trump announced the US would reverse its decision and not join in the statement after all.

At the news conference, Trudeau also said Canada will "move forward with retaliatory measures" on July 1 in response to the Trump administration's decision to impose tariffs on steel and aluminum imports from Canada, the European Union and Mexico.

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