An Air Force representative on Monday denied a report that B-52 bombers rigged with nuclear weapons are being prepared for 24-hour alert.

The report quoted a senior Air Force official as saying the preparations were already underway. If the bombers were to be put on 24-hour alert, it would be the first time since the Cold War.

In the report by security news website Defense One, Gen. David Goldfein, the Air Force's chief of staff, said U.S. military leaders are reacting to new threat levels.

"The world is a dangerous place and we've got folks that are talking openly about use of nuclear weapons," he said, according to the report. Goldfein said that while no official order had been given to put nuclear bombers on alert, preparations were underway.

"This is yet one more step in ensuring that we're prepared," he said during a tour of Air Force bases home to nuclear bombers, according to Defense One. "I look at it more as not planning for any specific event, but more for the reality of the global situation we find ourselves in and how we ensure we're prepared going forward."

Laura M. McAndrews, a spokeswoman for the Air Force, denied the report and told CNBC that there were no plans or preparations to put the bombers back on 24-hour alert.

Refurbishments are reportedly being made to Barksdale Air Force base in Louisiana, home to the 2d Bomb Wing and Air Force Global Strike Command, which oversees U.S. nuclear forces.

Beds are being installed for more than 100 crew members that would operate as many as nine bombers positioned on the runway. Defense One also reported that Barksdale and other bases with nuclear bombers are preparing storage facilities to house a new model of nuclear cruise missile.

McAndrews said that updates to base infrastructure "are necessary to maintain a baseline level of readiness."

"We do this routinely as part of our organize, train and equip mission so our forces are ready to respond when called upon," she said.

Read more of Defense One's article here.