On Thursday, the White House released President Donald Trump's plan to impose tariffs on steel and aluminum imports from all countries except for Canada and Mexico right ahead of the White House signing ceremony.

The Washington Examiner reports that Trump's plan will "give him plenty of options for future changes — including a possible increase in the tariff levels — depending on U.S. economic conditions and the actions of other U.S. trading partners."

At the signing ceremony, Trump said, "We have to protect and build our steel and aluminum industries, while at the same time showing great flexibility and cooperation toward those that are really friends of ours, both on a trade basis and a military basis."

Ahead of President Trump signing the pair of executive orders, a senior White House official told reporters that the tariffs were are needed for economic and national security reasons.

“This has been extremely and carefully vetted, well-litigated, and well-actualized,” the official said of the plan. “Nobody, particularly in the beltway, should express any kind of surprise at the actions we are taking. These have been some of the most well-discussed actions … probably in the history of trade actions.”

The Associated Press reports that "all countries affected by proposed U.S. tariffs on steel and aluminum have been invited to negotiate exclusions from the measures," according to officials briefed on Trump's plans.

Immediately following the signing, Arizona Republican Senator Jeff Flake immediately announced that he would seek to nullify Trump's plan through legislation.

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