China, U.S., U.K., France and Russia pledge to avoid nuclear war

Five of the world's largest nuclear powers pledged on Monday to work together toward 'a world without nuclear weapons' in a rare statement of unity amid rising East-West tensions.

"A nuclear war cannot be won and must never be fought," said the joint statement, which was issued simultaneously by the United States, Russia, China, the United Kingdom and France. "As nuclear use would have far-reaching consequences, we also affirm that nuclear weapons -- for as long as they continue to exist -- should serve defensive purposes, deter aggression, and prevent war."

The statement also stressed the importance of preventing conflict between nuclear-weapon states from escalating, describing it as a "foremost responsibility."

The statement comes as tensions between the world powers have risen to heights rarely seen in recent decades. In Europe, Russia is massing troops along its border with Ukraine, raising alarms in Washington, London and Paris. And in Asia, increased Chinese military activity around the self-governed island of Taiwan has spiked tensions between Beijing and Washington and its Pacific allies.

The statement released by the five powers, also known as the P5, as permanent members of the United Nations Security Council, called on all states to create a security environment "more conducive to progress on disarmament with the ultimate goal of a world without nuclear weapons with undiminished security for all."