President Donald Trump on Tuesday will announce his move with the Iran nuclear deal.

Should he pull out of the nuclear deal, global crisis could occur.

Will he choose his “America First” philosophy?

The decision, to be announced at the White House at 2 p.m. ET Tuesday, will be a pivotal moment for Trump’s presidency.

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“Trump is expected to announce on Tuesday that he will allow sanctions to go forward on Iran, a first step toward withdrawing from the deal, a US official and a person familiar with the plan” told CNN.

“However, the sanctions could take months to go into effect as the US government develops guidance for companies and banks. That could keep open a narrow window for America’s European allies to continue trying to broker a broader deal that could keep Trump on board.”

The officials cautioned that nothing is final until Trump makes his announcement.