The Trump administration said Wednesday that it would hold Iran “accountable” for its recent ballistic-missile launch, threatening an unspecified response to what it called a violation of U.N. restrictions.

In a brief statement read during the regular White House press briefing, Michael Flynn, President Trump’s national security adviser, said the administration was “officially putting Iran on notice” for the test launch and for what he called Iran’s threatening and destabilizing actions in support of Houthi rebels seeking to overthrow a U.S.-backed government in Yemen.

The statement marked the new administration’s first public foray into an issue on which Trump had promised to take a hard line. It followed U.S. military ground action Saturday against al-Qaeda’s affiliate in Yemen — the first counterterrorism mission approved by Trump — in which a U.S. service member was killed.

Flynn said Iran had been “emboldened” by “weak and effective” U.N. and Obama administration policies, including agreements such as the 2015 deal designed to prevent Iran from developing a nuclear weapon.

[Republicans cheer Flynn putting Iran ‘on notice’]

In a background briefing after the statement, senior administration officials emphasized that what they called Iranian “provocations,” and the threat to do something about them, were unrelated to the nuclear agreement.

“These missile concerns are separate and apart” from the nuclear deal, one official said. “We’re keeping a very big line between these issues. There should be no doubt about that.”

While a number of Republican lawmakers have called for the agreement to be torn apart, Trump avoided that language during his campaign, calling it a “bad deal” that he intended to review.

Iran made no public statement in response but said the missile test was discussed during a high-level national-security meeting Wednesday.

“We discussed Iran’s missile tests and . . . reaffirmed that Iran would not wait for any country’s permission in defense issues,” Deputy Foreign Minister Majid Ravanchi said, according to Iran’s Mehr News Agency. He also repeated an earlier statement that Tehran plans to take “reciprocal measures” in response to Trump’s new temporary ban on U.S. entry for individuals from seven Muslim-majority countries, including Iran.

Iran’s launch Sunday of a medium-range Khorramshahr missile ended in failure, with the missile reportedly traveling about 600 miles before exploding in the air.

The United States called for an emergency meeting of the U.N. Security Council. Following the Tuesday session, Nikki Haley, the new U.S. ambassador to the United Nations, said the world should be “alarmed” by the test and called for unspecified U.N. action.

Flynn and other officials said the launch violated U.N. Security Council Resolution 2231, which gave international blessing to the Iran nuclear deal. Part of the deal was the elimination of previous resolutions prohibiting all ballistic-missile activity. Instead, an annex to the deal calls on Iran “not to undertake any activity related to ballistic missiles designed to be capable of delivering nuclear weapons, including launches using such ballistic missile technology” for the next eight years.

Iran maintains that, because it does not have a nuclear weapons program, development and testing of non-nuclear-related ballistic missiles — which it says are for conventional defense — are not prohibited.

A senior Trump administration official said that the nuclear capability of the missile was a “factual and technical question that doesn’t depend upon what procedural mechanism has or has not been used in the past to make decisions on what to do about it.”

“These are things that are inherent in the physics,” the official said. “It is an objectively knowable thing, irrespective of what governments decide to do.”

Suzanne Maloney, deputy director of the foreign policy program at the Brookings Institution, said that there is widespread international consensus, without the United States, that Iran’s missile test is not an explicit violation of the resolution, but that “there is a wider consensus about the undesirability of Iran’s missile activities than there is about how to respond.”

Some U.S. lawmakers who have questioned the nuclear deal were quick to praise the administration for taking a tough line. Sen. Bob Corker (R-Tenn.), chairman of the Senate Foreign Relations Committee, said in a written statement that Iran will “no longer . . . be given a pass for its repeated ballistic missile violations, continued support of terrorism, human rights abuses and other hostile activities that threaten international peace and security.”

Israeli Prime Minister Benjamin Netanyahu also congratulated the administration for its words about Iran, saying the missile test was a “flagrant violation” of the U.N. resolution. “Iranian aggression must not go unanswered,” he said.

Flynn and other officials also held Iran responsible for “destabilizing” activity in Yemen, where Saudi Arabia is defending a government under attack from what it says are Iranian-backed Houthi rebels. The Obama administration had criticized Iran for helping to arm the rebels but did not consider the aid decisive in what has become a years-long war.

On Monday, a Saudi warship patrolling off the Yemen coast was attacked by a rebel “suicide boat” that exploded after striking the ship. Two Saudi sailors were killed.

The Trump administration’s statements hewed closely to the views of the Saudi government, whose King Salman spoke with Trump on Sunday, in holding its archenemy Iran responsible for the Houthi rebellion.

“We assess Iran seeks to leverage this relationship with the Houthis to build a long-term presence in Yemen,” said a Trump official, who like others at the briefing spoke on the condition of anonymity imposed by the administration. “This support risks expanding and intensifying the conflict in Yemen, which is not good for the people of the area, creates further instability, risks greater violence and will lead to unending conflict.”

In response to repeated questioning, the officials declined to specify what actions were under consideration. “There are a large range of options available . . . from financial and economic to pursuing other options related to support for those that are challenging and opposing Iranian malign activity in the region,” one official said. “We are in a deliberative process.”

The official said that the White House had received “input” from the State Department and other agencies before making the Iran announcement and that they would be included in ongoing deliberations about further steps.

“There are a large number of options available to the administration,” he said. “We’re going to take appropriate action, and I will not provide any further information today.”

“The important thing here is, we are communicating that Iranian behavior needs to be rethought by Tehran,” he said, adding that the administration was “considering these things in a different perspective.”

Carol Morello contributed to this report.