"These assets will join the USS Abraham Lincoln Carrier Strike Group and a US Air Force bomber task force in the Middle East region in response to indications of heightened Iranian readiness to conduct offensive operations against US forces and our interests," the Pentagon said in a statement.
On Friday a defense official reiterated that the Iranian threat "is still real and credible and we're taking it seriously."
The deployment of the Arlington and Patriot missile battery is "meant to be defensive in nature," the official said.
The official and the Pentagon did not disclose where the additional US missiles will be sent but called it a "prudent measure to protect our forces."
The US posturing of forces "provides us with options should deterrence fail and we need to respond," the official added.