MOSCOW (AP) — A senior Russian diplomat says Washington's plans for modernizing its nuclear arsenal could lower the threshold for using nuclear weapons.

Deputy Foreign Minister Sergei Ryabkov said Thursday the U.S. Nuclear Posture Review "directly undermines, if not destroys strategic stability."

The document released last week asserts that Russian strategy emphasizes the potential coercive and military uses of nuclear weapons, and calls for two new U.S. capabilities in response — a sea-launched nuclear cruise missile and a "low-yield" warhead for submarine-launched ballistic missiles.

Ryabkov rejected the U.S. claims about Russian intentions as unfounded in remarks carried by Russian news agencies. He warned the U.S. may view the prospective low-yield nuclear warhead as a battlefield weapon for use in a limited conflict, something that would dramatically lower the threshold for nuclear weapons use.