White House National Security Advisor Jake Sullivan said Sunday the US will press on with its retaliation against Iran-backed groups in Iraq and Syria.

Asked whether the United States would rule out the possibility of striking Iran directly, Sullivan told NBC, "it would not be wise for me to talk about what we're ruling in and ruling out."

"If (Iran) chose to respond directly to the United States, they would be met with a swift and forceful response from us," he said.

Iran's foreign ministry spokesman Nasser Kanani hit back on Monday, saying: "The Islamic Republic has shown that it has always reacted decisively to any threat to its security, territorial integrity and sovereignty."

Iran "will not hesitate to use its capabilities" to respond to any attacks on its soil, said Kanani during his weekly press briefing.

He nonetheless reiterated that Iran "does not seek to aggravate tensions and crises in the region".

Regional tensions have soared since the October 7 outbreak of the Israel-Hamas war, drawing in Iran-backed groups in Iraq, Syria, Yemen and Lebanon.

The US military said it carried out airstrikes against five missiles in Yemen on Sunday.

The strikes came a day after US and UK forces launched a wave of air raids against Yemen's Iran-backed Huthis -- their third round of joint military action in response to the rebels' persistent attacks on shipping.

The Huthis say their attacks in the Red Sea are in solidarity with Palestinians in war-battered Gaza.

The US military struck targets in Syria and Iraq overnight on Friday to Saturday, in retaliation for a January 28 drone attack on a base in Jordan that killed three US soldiers.

The Islamic republic condemned the strikes in Yemen, Syria and Iraq.

President Joe Biden has blamed "radical Iran-backed militant groups" for the attack in Jordan, but said the United States does not seek a wider conflict in the Middle East.