The Pentagon has sent six B-52 heavy bombers to a British base in the Indian Ocean to stand by in case tensions with Iran escalate into a military confrontation.

The nuclear-capable bombers at Diego Garcia will be within striking distance of the Persian Gulf but out of the range of Iranian missiles.

While the Cold War-era strategic bombers can carry nuclear-tipped, air-launched cruise missiles, more recently, they have been used to drop large numbers of conventional bombs in Iraq and Afghanistan, including a 2018 strike that dropped 24 smart bombs on Taliban positions, setting a record for the most guided munitions ever dropped from a B-52.

In 2016, U.S. Air Force B-52s, flying out of the al Udeid Air Base in Qatar, conducted airstrikes against Islamic State targets in Iraq and Syria.

"For operational security, we are not discussing forces flowing into or out of the U.S. Central Command area of responsibility at this time," said Cmdr. Rebecca Rebarich, a Pentagon spokeswoman, in response to media inquiries.

The B-52s are part of a regional U.S. military buildup that includes more than 3,500 troops from the 82nd Airborne Division that are headed to Kuwait and about 2,400 Marines from the 26th Marine Expeditionary Unit aboard the amphibious assault ship USS Bataan.

The recent deployments will bring the total number of U.S. forces in the Persian Gulf region to roughly 80,000.