Story highlights Flynn fires off dramatic warning but Trump team yet to frame options on Iran

Sharp tone marks departure from Obama dialogue

Washington (CNN) The Trump administration is getting tough with Iran -- but can't yet say how it will back up its rhetoric.

National Security Adviser Michael Flynn made a surprise, first-on-camera appearance Wednesday, using the authority of the White House briefing room to send a strong message to the leaders of the Islamic Republic and the wider Middle East.

"As of today, we are officially putting Iran on notice," Flynn said, in a statement condemning a recent Iranian ballistic missile launch and attacks on Saudi and Emirati vessels by Yemeni-based Houthi rebels, which are backed by Iran.

Flynn also spoke of threats to the US and allied shipping in the Red Sea, in remarks that left little doubt that an era of dialogue between the Obama administration and Iran, which thawed more than 30 years of boiling antagonism and proxy warfare, is now over.

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Flynn intended to make clear that the new management in the White House would not tolerate what it sees as Iran's destabilizing activity throughout the wider Middle East, following Republican claims that the last White House did just that to shield its legacy-enhancing nuclear deal.

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