(CNN) For the second day in a row, the Senate pushed back on President Donald Trump, showing stiff resistance to his key policy decisions on tariffs and NATO even as the President is at a summit in Europe wrestling with allies over those same issues.

Senators voted overwhelmingly Wednesday calling on Trump to get congressional approval before using national security as a reason for imposing tariffs on other nations, as he did recently with steel and aluminum levies against Mexico, Canada and the European Union

The bipartisan 88-to-11 tally on the non-binding resolution sends a message to the White House about how frustrated senators are over Trump's disruptive moves on tariffs.

However, future efforts to pass enforceable legislation likely face an uphill battle over Trump's objections.

"Let's be clear, this is a rebuke of the President's abuse of trade authority," said Sen. Jeff Flake, an Arizona Republican and a frequent and vocal critic of Trump's policies. "Can you imagine being Canada and being told your steel and aluminum exports to the United States (are) a national security threat?"

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