The weapon has a maximum yield of 360 kilotons, compared to the 15-kiloton bomb dropped on Hiroshima on 6 August 1945, which killed an estimated 140,000 people.
It would also be about 14 times bigger than the 25-kiloton bomb dropped on Nagasaki several days later in 1945, which killed around 74,000 people.
The bomb would take existing warheads and place them in newly designed housings and it is not yet clear what that would cost, reported BreakingDefense.com.
The bomb would most likely be carried by a B-2 Stealth bomber and not a fighter jet.
“Today’s announcement is reflective of a changing security environment and growing threats from potential adversaries,” Assistant Secretary of Defense for Space Policy John Plumb said in a statement.
“The United States has a responsibility to continue to assess and field the capabilities we need to credibly deter and, if necessary, respond to strategic attacks, and assure our allies.”
Pentagon notes state that the bomb would be deliverable by modern aircraft and would give the White House further options to strike hard and large-area military targets,
The announcement comes amid a deepening war in the Middle East between Israel and Hamas. The US also conducted a detonation experiment at a nuclear test site in Nevada earlier this month.
“They will help reduce global nuclear threats by improving the detection of underground nuclear explosive tests,” said Corey Hinderstein, the deputy administrator for defense nuclear nonproliferation at the National Nuclear Security Administration.