The new deployment includes Patriot missile batteries, reconnaissance aircraft and accompanying necessary forces to provide further deterrence against what the Pentagon believes is a rising Iranian threat against US troops in the region, according to the official and another US official directly familiar with the deployment proposal.
Shanahan, as acting secretary of defense, has the authority to sign deployment orders, but major deployments are typically briefed to the President.
The White House did not respond for comment.
The Trump administration is also considering using a pre-existing rule that would allow it to expedite arms sales to Saudi Arabia, Tehran’s regional foe, as part of its effort to counter Iran, according to two US officials.
The arms announcement could come as early as Friday.
The two moves signal an intensified push against Tehran that is likely to raise concerns on Capitol Hill, where lawmakers have questioned the administration’s threat assessment about Iran and expressed concern that the military build-up could lead to an accidental confrontation.
Shanahan and other administration officials have said the administration’s focus is on deterrence and the protection of US forces in the region.
This story is breaking and will be updated
CNN’s Ryan Browne contributed to this report