The U.S. Navy is going to have its Virginia-class attack submarines be armed with nuclear warheads, marking a history shift in how the submarines are used.

“While Virginia-class submarines can use conventional deterrence to keep adversaries in check, a sub-launched cruise missile with a nuclear warhead would be incorporated into Virginias and give national command authority additional escalation control,” Rear Adm. John Tammen, Director, Undersea Warfare Division, told Congress.

The new weapon, part of the Trump administration's recent Nuclear Posture Review, is likely to bring a new element to the Pentagon’s current nuclear weapons deterrence posture. Currently, only the Ohio class and the emerging Columbia-class are capable of firing nuclear weapons.

The Virginia submarines can currently fire Tomahawk missiles and torpedoes but by adding nuclear weapons, it would give combatant commanders new options and expand its mission, Tammen added.