File photo taken on Dec. 8, 1987 shows US president Ronald Reagan and Soviet leader Mikhail Gorbachev signing the Intermediate-Range Nuclear Forces Treaty in the White House in Washington D.C., the United States. (Xinhua)

"The U.S. withdrawal from the INF Treaty today deals a great blow to nuclear arms control and global security, we are sleepwalking into a new arms race," tweeted William Perry, former U.S. defense secretary.

WASHINGTON, Aug. 3 (Xinhua) -- The United States on Friday formally withdrew from the Intermediate-Range Nuclear Forces (INF) Treaty with Russia, a move experts say will throw international security into more uncertainty.

William Perry, former U.S. defense secretary, tweeted that "the U.S. withdrawal from the INF Treaty today deals a great blow to nuclear arms control and global security, we are sleepwalking into a new arms race."

Washington unilaterally started the withdrawal process in early February, citing Russia's violation of the deal, inked in 1987 between the United States and the Soviet Union on the elimination of intermediate-range and shorter-range missiles.

Moscow, which has repeatedly denied Washington's accusation, also suspended its participation in the INF Treaty, the first-ever pact reached by the two sides on nuclear disarmament and a major step forward in restricting arms race.

"The current course will lead to a less stable and secure world. The United States and Russia will be less able to predict future developments on the other side and thus will have to make expensive worst-case assumptions," noted Steven Pifer, a nonresident scholar with the Brookings Institution.

"Blowing up the INF Treaty with no substitute arms control plan in place could open the door to a dangerous new era of unconstrained military competition with Russia," said Daryl Kimball, executive director of the Arms Control Association.

In fact, the worries are not over-reacting. Hours after the collapse of the historic arms control pact, Pentagon announced that the United States will fully develop ground-launched conventional missiles.

"INF-class missiles, whether nuclear-armed or conventionally-armed, are destabilizing because they can strike targets deep inside Russia and in Western Europe with little or no warning. Their short time-to-target capability increases the risk of miscalculation in a crisis," Kimball warned.

UN Secretary-General Antonio Guterres also lamented that with the demise of the INF Treaty, the world lost an invaluable brake on nuclear war.

What's more, Washington's decision to leave the INF Treaty also prompted concerns about the fate of the New Strategic Arms Reduction Treaty (New START), which will expire in 2021.

The U.S. government thus far has shown no sign to extend the New START, which puts limits on the number of U.S. and Russian long-range nuclear warheads and launchers.

"Such a treaty is extremely important from a political point of view because it is effectively the only instrument today that allows the two sides to inspect one another and creates a certain level of trust-trust that no one is insidiously developing additional nuclear material in some basement, that the data that the two sides exchange correspond to reality," Viktor Murakhovsky, a retired Russian colonel, told National Interest recently.

"Allowing New START to lapse with nothing to replace it risks creating a destabilizing vacuum in nuclear arms control," noted Iain King, a visiting fellow at the Center for Strategic and International Studies, a Washington-based think tank.

"Extending the New START until 2026 is the choice that will best serve long-term goals, as the extension can be used to improve the nuclear arms reduction regime, strengthen nuclear control and verification systems," King added in a recently published article.

Experts worry that the annulment of the nuclear control pacts will eventually lead to a more complex and dangerous relationship between Washington and Moscow in the future.

"Perhaps then they will recall the lessons of the 1960s and 1980s that arms control, however imperfect, can offer a useful tool for managing great power competition," Pifer said.