The US has tested a missile previously banned under a now-defunct pact with Russia which limited the use of nuclear and conventional medium-range weapons
The US has tested a missile previously banned under a now-defunct pact with Russia which limited the use of nuclear and conventional medium-range weapons DoD / Scott HOWE

Moscow on Tuesday accused the United States of ramping up military tensions with a new missile test, weeks after the countries tore up a Cold War-era pact and sparked fears of a fresh arms race.

Washington and Moscow ditched the Intermediate-Range Nuclear Forces (INF) treaty this month after accusing each other of violating the deal.

Russia's deputy foreign minister Sergei Ryabkov said the new US test was a "cause of regret".

"The US has obviously taken a course towards escalation of military tensions. We won't react to provocations," Ryabkov told state news agency TASS.

The US Department of Defense announced on Monday it had tested a type of ground-launched missile that was banned under the 1987 INF agreement, which limited the use of nuclear and conventional medium-range weapons.

The missile was launched from the US Navy-controlled San Nicolas Island off the coast of California.

"We will not allow ourselves to get drawn into a costly arms race," Ryabkov said.

He said the test showed Washington had been working on such missiles long before its official withdrawal from the deal.

Ryabkov added that Moscow would refrain from using such missile systems "if and when we get them, as long as the US does not deploy them anywhere in the world".

Speaking in France Monday before news of the US test launch broke, President Vladimir Putin also said that Russia would only deploy medium- or shorter-range missiles in response to similar moves from the US.

"If the United States produces such offensive systems, we will also do so," Putin said at a press conference before meetings with French leader Emmanuel Macron.

Moscow and Washington have long criticised the treaty but Putin said it was the US that made the decision to "unilaterally" withdraw.

Deadly explosion in Russia

The missile tested on Sunday was a version of the nuclear-capable Tomahawk cruise missile. The ground-launched version of the Tomahawk was removed from service after the INF was ratified.

This month Secretary of Defense Mark Esper said the US had already begun work to develop "mobile, conventional, ground-launched cruise and ballistic missile systems".

"Now that we have withdrawn, the Department of Defense will fully pursue the development of these ground-launched conventional missiles as a prudent response to Russia's actions," Esper said.

But he also stressed the US was not embarking on a new arms race.

"The traditional sense of an arms race has been in a nuclear context," he said.

"Right now, we don't have plans to build nuclear-tipped INF-range weapons. It's the Russians who have developed non-compliant likely, possibly nuclear-tipped weapons," he said.

The US launch came weeks after a deadly explosion at a testing site in the far north of Russia, which Western experts linked to Moscow's attempts to develop a nuclear-powered missile.

The blast killed five scientists and caused a spike in radiation levels, though Russian authorities have remained tight lipped on the nature of the explosion.

US experts have said it could be linked to testing of the "Burevestnik" cruise missile, touted by Putin earlier this year.

The INF banned all land-based missiles that could travel between 500 and 5,500 kilometres (310 and 3,400 miles), in an effort to abolish the class of nuclear arms that then most threatened Europe.