The American secretary of defense, Lloyd Austin, said Sunday that he is ordering additional U.S. military assets to the Middle East in anticipation of what he said was the “prospect of a significant escalation of attacks on our troops throughout the region.”

In an appearance Sunday morning on ABC’s “This Week,” Mr. Austin warned any groups or countries in the region not to try and take advantage of the war in Israel. While no groups were mentioned by name, there is growing fear that Iranian-backed Hezbollah may attempt to open a second front in the war on Israel’s northern border with Lebanon.

“If any group or any country is looking to widen this conflict and take advantage of this very unfortunate situation that we see, our advice is, don’t,” he said. “We maintain the right to defend ourselves and we won’t hesitate to take the appropriate action.”

Separately, Secretary of State Blinken said the increase in American forces should not be seen as a provocation but rather a signal of the country’s intention to protect its forces wherever they are posted and secure the right of Israel to defend itself against terrorism.

“We’re taking every measure to make sure that we can defend them and if necessary, respond decisively,” Mr. Blinken said in an appearance on CBS’s “Meet the Press.” “It’s not at all what we’re looking for — not all we want — but we’ll be prepared, if that’s what they choose to do.”

The Pentagon announced Saturday that a second aircraft carrier strike group led by the USS Dwight D. Eisenhower would join USS Gerald R. Ford carrier strike group already stationed in the Eastern Mediterranean.

Mr. Austin also said he will deploy a Terminal High Altitude Area Defense, or THAAD, battery as well as additional Patriot battalions to locations throughout the region to increase protection of U.S. forces. An unspecified number of American troops were also given “prepare to deploy” notices should they be needed to buttress the assets already in the region.

Twice in the last week, American garrisons in Iraq and Syria have come under assault by Iranian-backed terrorists in the region. Also last week, an American warship headed south out of the Suez Canal intercepted as many as four cruise missiles and 15 drones launched from Yemen by Iranian-backed Houthi rebels. The missiles were headed north toward Israel when they were shot down.