National Security Adviser Michael Flynn Puts Iran 'on Notice'

— -- Making an appearance at Wednesday’s White House press briefing, National Security Adviser Michael Flynn delivered a stern warning to Iran for recent weapon testing and actions by state-supported militants, saying that the United States is putting the country “on notice.”

"The Trump administration condemns such actions by Iran that undermine security, prosperity, and stability throughout and beyond the Middle East and place American lives at risk," said Flynn. "As of today we are officially putting Iran on notice."

A U.S. government official confirmed to ABC News on Monday that Iran tested a medium-range ballistic missile over the weekend that exploded after travelling 550 miles. The official classified the event as a failed test. A United Nations Security Council Resolution bars Iran from undertaking “any activity related to ballistic missiles capable of delivering nuclear weapons, including launches using ballistic missile technology.”

On Tuesday after a meeting of the U.N. Security Council, U.S. Ambassador to the U.N. Nikki Haley classified the action as “absolutely unacceptable.”

“I will tell the people across the world that is something we should be alarmed about,” said Haley. “The United States is not naive. We are not going to stand by. You will see us call them out as we said we would, and you're also gonna see us act accordingly.”

Iran Defense Minister Hossein Dehghan later defended the test in comments Wednesday, claiming it did not violate the resolution. He was quoted by Iran’s Tasnim News Agency saying, “The recent test was in line with our programs, and we will not allow any outsider to interfere in our defense affairs.” The country has further claimed that the missiles are not designed to carry nuclear warheads.

Flynn’s comments at the White House also included a reference to a suicide attack Monday in which a Saudi Naval frigate in the Red Sear was rammed by Houthi militants whom he claimed were "Iran-supported." Two Saudi crew members were killed and three others were injured.

Flynn added that these recent actions came after a “series of incidents in the past six months” in which several nations' ships were targeted and threatened.

The remarks additionally took aim at the administration of former President Barack Obama, which Flynn said “failed to respond adequately to Tehran’s malign actions.”

“President Trump has severely criticized the various agreements reached between Iran and the Obama Administration, as well as the United Nations – as being weak and ineffective,” said Flynn, who noted that Iran was feeling “emboldened.”

ABC News’ Katherine Faulders and Luis Martinez contributed to this report.