(CNN) Arizona Republican Sen. Jeff Flake has threatened to introduce legislation to nullify the President's tariffs if they are anything like what Donald Trump is predicting.

"I'm going to -- as soon as it comes out if it is anything approximating what he's talked about -- introduce legislation to nullify it. I'm assuming I won't be the only one to do that," the frequent Trump critic told reporters Thursday.

Flake, like many Republicans, has expressed deep concerns about Trump's plans to issue new tariffs on aluminum and steel and says he's ready to fight legislatively if needed.

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