Sen. John McCain (R-Ariz.) took to social media Saturday to reassure United States allies that America stands with them, "even if our president doesn't."

McCain's message came after President Donald Trump withdrew the U.S. endorsement of a joint statement from the G-7 summit on trade and tariffs.

What did McCain say?

He tweeted on behalf of the U.S.:

Reaction to McCain's tweet was split. Many claimed McCain's statement undermined Trump on the world stage as he works to fix what he believes are longstanding trade imbalances between the U.S. and its allies.

Others, however, thanked McCain for his message.

Why did Trump act against the G-7?

Following his departure from the summit, Trump said on social media he had "great meetings and relationships" with the six other G-7 leaders.

"They fully understand where I am coming from. After many decades, fair and reciprocal Trade will happen!" Trump said, adding:

However, the sentiment quickly changed after Canadian Prime Minister Justin Trudeau said his country would move forward with "retaliatory" tariffs, which he said are coming in direct response to new controversial tariffs Trump recently put in place.

Trudeau's announcement, which came after the G-7 leaders signed a joint statement on trade, obviously frustrated the U.S. envoy, spurring Trump to revoke the U.S. endorsement of the statement. He also called Trudeau "very dishonest" and "weak."

During the summit, Trump said U.S. allies treat America "like a piggy bank" and vowed to keep in place the new tariffs.