UPDATE 1-B-52 bombers to be part of extra U.S. forces sent to Middle East

The U.S. military said on Tuesday that B-52 bombers will be part of additional forces being sent to the Middle East to counter what the Trump administration says are "clear indications" of threats from Iran to U.S. forces there.

White House national security adviser John Bolton said on Sunday that the United States was deploying a carrier strike group and a bomber task force to the Middle East. Captain Bill Urban, a spokesman for U.S. Central Command, said that the bomber task force would consist of B-52 bombers.

U.S. officials, speaking on the condition of anonymity, said four B-52s would be deployed, though that number could change. The United States has regularly maintained a bomber presence in the region, and B-1 bombers were there as recently as last month. The military also confirmed that the Abraham Lincoln carrier strike group had already been scheduled to go to the Middle East, but that its movement was "expedited" due to the tension with Iran.

Iran's top security body dismissed the U.S. plan to send forces to the region as "psychological warfare." Announcing details of the force on Tuesday, the U.S. military did not provide specific details of intelligence it may have about an Iranian threat.

U.S. Central Command, which is responsible for U.S. military operations in the Middle East and Afghanistan, requested additional forces following "recent and clear indications" that Iranian and proxy forces were making preparations to possibly attack U.S. forces in the region, Urban said. He said the credibility of those threats was based on sources and methods through which the information was obtained, something the U.S. military was not able to discuss.

The military has said the threat to U.S. forces was on land and at sea, but declined to provide further details. "U.S. Central Command continues to track a number of credible threat streams emanating from the regime in Iran throughout the CENTCOM area of responsibility," Urban said.

U.S. officials have told Reuters that the intelligence was based on specific and "credible" threats to U.S. forces in Iraq, Syria and the broader region. (Reporting by Idrees Ali, Editing by Franklin Paul and Alistair Bell)