Story highlights He has repeatedly disparaged the deal

Trump also slapped new sanctions on 14 individuals and entities

Washington (CNN) President Donald Trump on Friday avoided upending the nuclear deal with Iran that he has repeatedly disparaged, agreeing to waive key sanctions the US lifted as part of the deal.

But Trump warned Friday in a statement that the waiver -- which must be issued every 120 days to keep the sanctions from kicking back in -- will be the last he issues and he delivered a stark ultimatum to European allies on Friday: "Fix the deal's disastrous flaws, or the United States will withdraw."

"I am waiving the application of certain nuclear sanctions, but only in order to secure our European allies' agreement to fix the terrible flaws of the Iran nuclear deal. This is a last chance," Trump said in a statement Friday. "In the absence of such an agreement, the United States will not again waive sanctions in order to stay in the Iran nuclear deal. And if at any time I judge that such an agreement is not within reach, I will withdraw from the deal immediately."

That threat to effectively pull the US from the deal if his latest demands are not met leaves the nuclear deal in its most precarious position yet since the landmark agreement to curb Iran's nuclear ambitions was brokered between the US, five other world powers and Iran in July 2015. And Trump warned Friday that "no one should doubt my word."

Trump coupled his waiver announcement with new sanctions on 14 Iranian individuals and entities that have committed human rights abuses or supported the country's ballistic missile programs, which are outside the scope of the nuclear deal. Many of those sanctions -- including one targeted at the head of Iran's judiciary -- were in response to the Iranian government's crackdown of peaceful protests that have swept the country in recent weeks.

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