Arizona Senator Jeff Flake introduced federal legislation Monday that would nullify President Donald Trump’s plan to impose tariffs on imported steel and aluminum.

In early March, Trump announced a plan to tax imported steel at 10 percent and aluminum at 25 percent. Mexico and Canada would be exempt as part of larger North American trade negotiations.

On the Senate floor Flake called the proposed tariffs a “disaster.”

“If implemented, these tariffs will do just what tariffs have always done, it’ll lead to job losses and will stymie economic growth,” he said.

This legislation faces an uphill battle. Even if it passes the Republican controlled House and Senate, Trump would need to sign the bill into law.

Ultimately two-thirds of the legislature would need to defy Trump’s wishes to override a presidential veto.

“I understand free trade is sometimes a challenge. I understand that it’s a challenge on the campaign trail,” said Flake, who is not running for re-election this year. “It’s often easier to point to a shuttered factory and blame trade or immigration or some other convenient scapegoat.”