WASHINGTON, Feb. 4 (Xinhua) -- The Pentagon said on Tuesday that U.S. Navy had deployed low-yield nuclear weapons, a move that critics believed will not contribute to strategic stability.

U.S. Department of Defense confirmed in a statement that U.S. Navy had fielded W76-2 low-yield submarine-launched ballistic missile (SLBM) warhead, adding that this capability would strengthen deterrence and support U.S. commitment to extended deterrence.

The statement noted that the deployment would demonstrate to potential adversaries that "there is no advantage to limited nuclear employment because the United States can credibly and decisively respond to any threat scenario."

The statement also referred to the 2018 Nuclear Posture Review, in which the Pentagon identified the requirement to "modify a small number of submarine-launched ballistic missile warheads" to address the conclusion that potential adversaries, like Russia, believe that employment of low-yield nuclear weapons will give them an advantage over the United States and its allies and partners.

A Jan. 29 article on the website of Federation of American Scientists first reported that U.S. ballistic missile submarine U.S.S. Tennessee had deployed W76-2 warhead on a small portion of its SLBMs, and the submarine conducted a deterrent patrol in the Atlantic Ocean starting at the end of 2019.

W76-2 warhead is a modification of the pre-existing W76-1 warhead, and the former is estimated to have an explosive yield of about five kilotons while the latter is about 90 kilotons.

Some critics concerned that deploying low-yield warheads is militarily unnecessary and brings high risk. What experts frequently raised is that mixing low and high yield nuclear weapons on the same platform would make the adversary impossible to tell the nature of incoming missiles in conflict scenarios, thus might lead to a full-sized response by the adversary.