JERUSALEM (AP) — After a weekend of retaliatory strikes, the United States on Sunday warned Iran and the militias it arms and funds that it will conduct more attacks if American forces in the Mideast continue to be targeted, but that it does not want an “open-ended military campaign” across the region.

“We are prepared to deal with anything that any group or any country tries to come at us with,” said Jake Sullivan, President Joe Biden’s national security adviser. Sullivan said Iran should expect “a swift and forceful response” if it — and not one of its proxies — “chose to respond directly” against the U.S.

Sullivan delivered the warnings during a series of interviews with TV news shows after the U.S. and Britain on Saturday struck 36 Houthi targets in Yemen. The Iran-backed militants have fired on American and international interests repeatedly in the wake of the Israel-Hamas war.

An air assault Friday in Iraq and Syria targeted other Iranian-backed militias and the Iranian Revolutionary Guard in retaliation for the drone strike that killed three U.S. troops in Jordan last weekend. The U.S. fired again at Houthi targets on Sunday.

“We cannot rule out that there will be future attacks from Iranian-backed militias in Iraq and Syria or from the Houthis,” Sullivan said. He said the president has told his commanders that “they need to be positioned to respond to further attacks as well.”

The U.S. has blamed the attack at the Tower 22 base in Jordan on Jan. 28 on the Islamic Resistance in Iraq, a coalition of Iranian-backed militias. Iran has tried to distance itself from the drone strike, saying the militias act independently of its direction.

Biden “is not looking for a wider war,” Sullivan said, when questioned about the potential for strikes inside Iran that would expand the conflict in the volatile region. But when asked about the possibility of direct escalation by the Iranians, he said: “If they chose to respond directly to the United States, they would be met with a swift and forceful response from us.”

While pledging to respond in a “sustained way” to new assaults on Americans, Sullivan said he “would not describe it as some open-ended military campaign.”

Still, he said, “We intend to take additional strikes and additional action to continue to send a clear message that the United States will respond when our forces are attacked or our people are killed.”

There will be more steps taken, he said. “Some of those steps will be seen. Some may not be seen.”

The U.S. attack on dozens of sites in Iraq and Syria hit more than 85 targets at seven locations. These included command and control headquarters, intelligence centers, rockets and missiles, drone and ammunition storage sites and other facilities that were connected to the militias or the Islamic Revolutionary Guard Corps’ Quds Force, the expeditionary unit that handles Tehran’s relationship with, and arming of, regional militias.

The Biden administration has so far appeared to stop short of directly targeting Iran or senior leaders of the Quds Force within its borders.