WASHINGTON — The Pentagon has ordered a second carrier strike group to the eastern Mediterranean Sea and is sending Air Force fighter jets to the region as Israel prepares to expand its Gaza operations, US Defense Secretary Lloyd Austin said in a statement Saturday.

The US warships are not intended to join the fighting in Gaza or take part in Israel’s operations, but the presence of two of the Navy’s most powerful vessels is designed to send a message of deterrence to Iran and Iranian proxies in the region, such as Hezbollah in Lebanon.

The movements are “part of our effort to deter hostile actions against Israel or any efforts toward widening this war following Hamas’s attack on Israel,” Austin said in the statement.

The first carrier strike group, led by the USS Gerald R. Ford, arrived off the coast of Israel last week.

Now the USS Dwight D. Eisenhower strike group, which deployed from Norfolk, Virginia, on Friday, is headed to the eastern Mediterranean. The aircraft carrier was initially set to sail for the waters of US European Command.

It is unclear how long the Ford will stay in the region once the Eisenhower carrier strike group arrives, one US defense official told CNN.

The Eisenhower, which is the flagship of the carrier strike group, will be joined by a guided-missile cruiser and two guided-missile destroyers, Austin’s statement said.

The Eisenhower can carry more than 60 aircraft, including F/A-18 fighter jets. The Ford can deploy more than 75 aircraft.

ABC News first reported the carrier strike group’s orders.

The Biden administration made clear that the carrier and its accompanying force are not there to engage in combat activities on behalf of Israel.

“There is no intention or plan to put American troops on the ground in Israel,” John Kirby, strategic communications coordinator for the National Security Council, said Thursday.

“We take our national security interests very seriously in the region,” he said, noting that the purpose of the bolstered force posture was “to act as a deterrent for any other actor, including Hezbollah, that might think that widening this conflict is a good idea.”

However, on Sunday, Kirby wouldn’t rule out sending in US troops to help free Americans who may be held hostage by Hamas in Gaza.

Speaking to “Fox News Sunday,” Kirby said there were “no plans or intentions to put US troops on the ground in the fight between Israel and Hamas,” but when pressed repeatedly on whether the administration was considering deploying troops to save Americans, he wouldn’t say no.

“What I won’t do is rule anything in or out when it comes to getting our hostages home,” he said. “We’re working on this literally by the hour.”

Kirby said Sunday that the US knows there are Americans being held hostage by Hamas — going beyond his comments Wednesday, when he said the US believed there were Americans among the hostages.

“We don’t even know how many exactly. A small handful we know, there could be more than we know, they could be in different groups, they could be moved around,” he said Sunday.

In addition, the 26th Marine Expeditionary Unit, a rapid reaction force capable of conducting special operations, is making preparations in case it is ordered closer to Israel to bolster the US’ force posture there, multiple US officials told CNN.

The unit, which is on board the amphibious assault ship USS Bataan, is composed of more than 2,000 Marines and sailors and would be capable of supporting a large-scale evacuation.

Among the mission essential tasks for a Marine Expeditionary Unit are evacuation operations and humanitarian assistance. No such order has been given yet to the unit, the officials said.

Meanwhile, US Air Forces Central on Saturday announced the deployment of F-15E fighter jets and A-10 ground-attack jets to the region.

The movement of the warplanes from the 494th Expeditionary Fighter Squadron and 354th Expeditionary Fighter Squadron, respectively, “bolster the US posture and enhance air operations throughout the Middle East,” an Air Force statement said. It did not give specific numbers of warplanes involved.

A US Central Command social media post said the A-10s will join another squadron of the aircraft already in the region. US Defense Secretary Austin’s statement said F-16 fighters have also been deployed to the region.

“By posturing advanced fighters and integrating with joint and coalition forces, we are strengthening our partnerships and reinforcing security in the region,” Lt. Gen. Alexus Grynkewich, 9th Air Force commander, said in a statement.

Defense officials have said repeatedly in recent days that the Pentagon will be able to flow in additional forces and assets to the region quickly as needed, as Israel continues to fight a war against the terrorist group Hamas. — CNN