The acting U.S. defense chief has vowed to hold Iran "accountable for any attack on U.S. forces or our interests," as Washington stepped up its rhetoric and said it was deploying an aircraft carrier battle group to waters near Iran.
In a post to Twitter on May 6, Patrick Shanahan, the acting secretary of defense, also accused Tehran of unspecified provocations.
"We call on the Iranian regime to cease all provocation. We will hold the Iranian regime accountable for any attack on U.S. forces or our interests," he wrote.
Shanahan's comments came a day after White House national-security adviser John Bolton said that the deployment of the USS Abraham Lincoln, and accompanying ships, along with a bomber task force, was intended to send Iran "a clear and unmistakable message."
He said the United States is “not seeking war with the Iranian regime” but that it is “fully prepared to respond to any attack, whether by proxy, the Islamic Revolutionary Guards Corps, or regular Iranian forces.”
The deployment of the carrier and bomber groups sends "a clear and unmistakable message to the Iranian regime that any attack on United States interests or on those of our allies will be met with unrelenting force," Bolton said in a May 5 press briefing.
A U.S. defense official told the Associated Press that the deployment followed "clear indications" that Iranian and Iranian proxy forces were preparing to possibly attack U.S. forces in the region.
The official, who spoke on condition of anonymity, said that the Pentagon approved the deployments and that U.S. forces at sea and on land were thought to be the potential targets. The official declined to be more specific.
Since taking office two years ago, President Donald Trump's administration has escalated its pressure on Iran, including pulling out of a key nuclear agreement that aimed to curtail Iran's nuclear ambitions.
Trump argued the deal was flawed because it did not include curbs on Iran’s development of ballistic missiles or its support for proxies in Syria, Yemen, Lebanon, and Iraq. Iran has expanded its missile program in recent years, particularly its ballistic missiles.
The U.S. administration recently announced it would not extend waivers allowing importers to buy Iranian oil without facing U.S. sanctions, in an attempt to reduce Iran's oil exports to zero.
It has also designated Iran's Islamic Revolutionary Guards Corps as a terrorist organization, marking the first time Washington has officially used that label on a foreign state institution.
The USS Abraham Lincoln and its strike group of ships and combat aircraft have recently been operating in the Mediterranean Sea.
There was no exact information on where the carrier group was headed, but Bolton referred to the U.S. Central Command region, which would mean the force is headed to the Red Sea and perhaps then to the Persian Gulf, where the U.S. Navy currently has no aircraft carrier.
Bolton's statement also suggested that Washington was deploying land-based bomber aircraft in the region.
In his post to Twitter, Shanahan said the deployments represented "a prudent repositioning of assets in response to indications of a credible threat by Iranian regime forces."