WASHINGTON, Feb 1 (Reuters) - President Donald Trump's national security adviser, Michael Flynn, said the United States was officially putting Iran on notice on Wednesday over its "destabilizing activity" after it test-fired a ballistic missile over the weekend.

"As of today, we are officially putting Iran on notice," Flynn told a White House briefing, without explaining exactly what that meant.

Flynn said the ballistic missile launch on Sunday was in defiance of a U.N. Security Council resolution that called on Iran not to undertake any activity related to ballistic missiles designed to be capable of delivering nuclear weapons.

(Reporting by Roberta Rampton; Writing by David Alexander; Editing by Doina Chiacu)

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