The Pentagon has ordered a number of military units put on alert for rapid deployment to the Persian Gulf, Fox News learned Friday.
Some are being told to be ready to deploy, if needed, within 96 hours' notice.
"A lot of things will start moving in the next week or so," a defense official told Fox News.
Defense Secretary Donald Rumsfeld ordered the Navy to prepare two aircraft carriers and two amphibious assault vessels for possible action in Iraq. The orders, sent in the last two days, require the Navy to have the vessels ready to sail to the Persian Gulf within 96 hours after a certain date, which was not revealed.
Rumsfeld has also ordered the USNS Comfort, a hospital ship based in Baltimore, to be activated and readied for possible deployment.
The aircraft carriers and the cruisers, destroyers and submarines that escort them would bring a powerful military force to the region, adding several warships, scores of strike aircraft and roughly 4,400 Marines to the forces already there.
One battle group told to get ready is attached to the aircraft carrier USS George Washington, which returned to port in Norfolk, Va., on Dec. 20 following a six-month deployment in the Gulf.
If the order to sail is given, that Atlantic carrier group would be joined in the Persian Gulf by either the USS Abraham Lincoln or the USS Kitty Hawk battle group, would be sent from the Pacific fleets. The Abraham Lincoln is in Perth, Australia, having just left the Persian Gulf. The Kitty Hawk is in port in Japan.
The defense officials declined to say which amphibious assault groups are most likely to be sent to conduct operations in Iraq. Those groups center on a large, carrier-like vessel that can launch helicopters and carry Marines.
Already in the region is the carrier USS Constellation and the amphibious assault ship USS Nassau, officials said.
Some units in the Air Force's Air Combat Command have also received "prepare to deploy" orders from the defense secretary, with planes due to leave the U.S. within the next 12 days.
They include F-15E Strike Eagles from Seymour-Johnson AFB in North Carolina, F-15C fighter-bombers, B-1 and B-52 bombers and AWACS (Airborne Warning and Control System) planes.
The B-52s will be deployed to Diego Garcia, a British airbase in the Indian Ocean, but all the other planes will be based in the Gulf.
B-2 bombers from Whiteman Air Force Base in Missouri, which flew to Afghanistan and back again on missions, are not currently scheduled for deployment.
Air Force bases that have received deployment orders are Ellsworth AFB in South Dakota, Moody AFB in Georgia, Langley AFB in Virginia and Nellis AFB in Nevada.
The Comfort, a 1,000-bed floating hospital, will initially sail with a crew of 61 civilian mariners and 225 Navy personnel, including enough doctors to support two operating rooms, said Marge Holtz, spokeswoman for the Navy's Military Sealift Command. Hundreds more will be flown to the ship as needed, she said.
The white-painted vessel, marked with red crosses, is equipped to handle combat casualties, including those injured in chemical or biological weapons attacks, Holtz said.
It may leave as early as Monday, Holtz said.
The ship was last deployed during the summer for exercises with U.S. allies in the Baltic Sea.
In the days after the Sept. 11 attacks, the Comfort sailed to the waters around Manhattan to treat people injured in the collapse of the towers. In the end, those services were not needed, as local hospitals were able to handle the survivors.
The vessel instead served as a floating hotel for rescue personnel working at the World Trade Center site, providing meals, beds and laundry service for more than 2,200 rescue workers.
The Comfort, a converted oil tanker, is only one of two hospital ships of its size. Its sister ship, the USNS Mercy, is based in San Diego.
The Associated Press contributed to this report.
Bret Baier currently serves as anchor of Fox News Channel's "Special Report with Bret Baier" (weeknights 6-7PM/ET), the top-rated cable news program in its timeslot. Based in Washington, D.C., he joined the network in 1998 as the first reporter in the Atlanta bureau. Click here for more information on Bret Baier.