A ballistic missile is launched and tested in an undisclosed location, Iran, March 9, 2016.

:: The United States slapped new economic sanctions against Iran on Tuesday over its ballistic missile program and said Tehran’s “malign activities” in the Middle East undercut any “positive contributions” coming from the 2015 Iran nuclear accord.

The measures signaled that the administration of President Donald Trump was seeking to put more pressure on Iran while keeping in place an agreement between Tehran and six world powers to curb its nuclear program in return for lifting international oil and financial sanctions.

The US government said it was targeting 18 entities and people for supporting what is said was “illicit Iranian actors or transnational criminal activity.”

Those sanctioned had backed Iran’s military or Iran’s Islamic Revolutionary Guard Corps (IRGC) by developing drones and military equipment, producing and maintaining boats, and procuring electronic components, it said. Others had “orchestrated the theft of US and Western software programs” sold to Iran’s government, the Treasury Department said.

“The United States remains deeply concerned about Iran’s malign activities across the Middle East which undermine regional stability, security, and prosperity,” the State Department said in a statement. It said the activities “undercut whatever ‘positive contributions’ to regional and international peace and security were intended to emerge” from the nuclear agreement.

Nuclear agreement

On Monday, the Trump administration said Iran was complying with the nuclear agreement but it was also in default of the spirit of the accord and Washington would look for ways to strengthen it.

It was the second time Trump certified Iranian compliance with the agreement since he took office in January, despite having described it as “the worst deal ever” during his 2016 presidential campaign, criticizing then-President Barack Obama whose administration negotiated the accord.

“Even as we continue to work to prevent Iran from ever obtaining a nuclear weapon, we cannot look away while Iran threatens our country and our allies in ways beyond their nuclear threat,” White House spokeswoman Sarah Sanders told reporters on Tuesday.

‘Poison the atmosphere’

The statement listed Iranian support for groups including Lebanon’s Hezbollah and the Palestinian Hamas movement, the Syrian government of President Bashar al-Assad and Houthi rebels in Yemen. Iran condemned Washington’s sanctions announcement as “contemptible and worthless.”

Iran “will reciprocate the move by imposing sanctions on a number of American natural and legal persons who have taken steps against the Iranian people and other Muslim nations in the region,” the foreign ministry said in a statement.

Iranian Foreign Minister Mohammad Javad Zarif told CBS News the sanctions “poison the atmosphere” and violate the “spirit” of the nuclear agreement. “We will look at it and see whether it violates the letter of the deal. And we will act accordingly,” he said.

The Trump administration is reviewing policy on Iran, not only looking at Tehran’s compliance with the nuclear deal but also its behavior in the region which Washington says undermines US interests in Syria, Iraq, Yemen and Lebanon.

Iranian Foreign Minister Mohammad Jawad Zarif speaks during a media conference at EU headquarters in Brussels on Monday, Feb. 15, 2016.