The UN secretary general has warned that the world has lost “an invaluable brake on nuclear war” with the expiry of a cold war-era arms control treaty on Friday.

The 1987 Intermediate-range Nuclear Forces (INF) treaty has kept nuclear missiles off European soil for more than three decades, but the US and Russia have failed to agree on how to keep it alive.

“This will likely heighten, not reduce, the threat posed by ballistic missiles,” António Guterres told reporters, adding that he was concerned about rising tensions between nuclear-armed states.

There have already been signs of a rekindled arms race in the class of weapons that the treaty banned: ground-launched missiles with ranges between 500 and 5,500km.

Nearly 2,700 of the cruise and ballistic nuclear missiles were destroyed under the treaty, removing a potent source of European insecurity. A targeted country would only have a few minutes warning of a launch, fueling paranoia and hair-trigger alerts on both sides of the Iron Curtain.

These weapons are now beginning to return.

“2 August marks the demise of the INF, which played a major role in enhancing stability in Europe,” said Laura Kennedy, the former US permanent representative to the conference on disarmament in Geneva. “Its termination could be both unsettling in Europe and could lead to new arms competition in other areas, such as Asia.”

The death of the INF comes amid aggressive nuclear weapon modernisation programmes being carried out by the US and Russia. Among the new weapons the US is contemplating is a nuclear bunker-buster, considered and then shelved under the George W Bush administration.

Russia has developed a land-based nuclear-capable cruise missile, which the US and its Nato allies say violates the INF range restrictions. Moscow initially denied the existence of the missile (known as the 9M729 or by its Nato designation, SSC-8) and then claimed its range was under 500km. It is thought likely to be a land-based version of the Russian navy Kalibr missile.

Russia’s Veliky Novgorod and Kolpino submarines fire the Kalibr cruise missiles from the eastern Mediterranean to hit Islamic State militants’ bases in Syria. Photograph: TASS / Barcroft Images

“They are dual-capable, they can carry nuclear weapons, they can reach European cities within minutes, they are mobile, hard to detect and they also reduce the threshold of any potential use of nuclear weapons in armed conflict,” the Nato secretary general, Jens Stoltenberg, said on Wednesday.

Russia’s refusal to scrap the weapon led Donald Trump to withdraw the US from the INF treaty, and the US is now developing at least three types of medium-range missiles, all of them designed for conventional warheads.

The first of these, believed to be a land-based version of the Tomahawk cruise missile with a 1,000km range, is due to be tested later this month. A second option, a medium-range ballistic missile, is due to be tested in November, with a range of up to 4,000km. Third, the army is planning to develop a new missile to be mounted on a mobile launcher, either a ballistic weapon or a hypersonic glide vehicle.

Pentagon officials have said the first weapon, the cruise missile, could be deployed within 18 months.

The prospect of the INF’s demise on Friday is viewed with little enthusiasm among UK officials, not least because the country falls in the range of the previously banned intermediate-range surface-to-surface missiles.

“It is a proper serious moment,” a Whitehall source observed, although there are no plans for the new administration of Boris Johnson to publicly mark the moment.

European officials say there has been limited discussion with their US counterparts on Nato policy after INF, in part because European policy was focused on saving the treaty.

Now that that has failed, UK officials argued there was unlikely to be an immediate return to a nuclear standoff between rival missile systems in Europe, as witnessed in the 1980s when US cruise and Pershing missiles were ranged against Soviet SS-20s.

The new Russian missile is nuclear capable, but not necessarily nuclear armed. They are presently believed to be organised in four battalions, only one of which is west of the Urals, though they are mobile allowing for rapid redeployment.

The US missiles are, for now, strictly conventional and Nato has said it has no intention of deploying nuclear missiles in Europe.

“We will not mirror what Russia is doing,” Stoltenberg said.

Furthermore, the Democratic majority leadership in the House of Representatives is opposed to the new US missiles, arguing there is no sign of a coherent strategy behind them, and has removed the $96m research and development budget for them from the House 2020 budget. The fate of the programmes now depends on the reconciliation process between the House and Senate versions.

It is unclear where a US cruise missile would be based. They would have to be located in eastern Europe to be in range of Russian targets, but one of Washington’s closest allies in the region, Poland, has insisted there would have to be unanimous Nato support for their deployment, which is unlikely.

Iskander-M missile launcher during a military exercise held by missile and artillery units of the Russian Eastern Military District’s 5th army at a firing range in Ussuriysk. Photograph: TASS / Barcroft Images

“Any US attempt to force the alliance to accept the missiles or to go around Nato and try to negotiate a bilateral agreement with an individual Nato member would be a significant source of division within Nato and one Russia would be eager to try and exploit,” said Kingston Reif, the director for disarmament and threat reduction policy at the Arms Control Association.

Administration hawks led by John Bolton, the US national security adviser, are also eyeing a possible Pacific deployment as a counter to Chinese medium-range missiles. The fact that China was outside the INF was one of the reasons cited by Bolton and others in their opposition to the treaty. But basing problems would also be a serious obstacle in the Pacific, as any host nation would become a primary target for a pre-emptive attack.

“Our east Asian allies aren’t exactly rushing to host these these missiles,” Reif said. They could be based on Guam, but that is 3,000km from China, and expose the population on the tiny US Pacific territory.

“There is no plan for what comes after INF,” said Pranay Vaddi, a former state department arms control official now at the Carnegie Endowment for International Peace. “Not having a plan or not at least forecasting that you’re thinking of a plan of what to do for European security and Asian security after the treaty is what strikes me as irresponsible.”

After the collapse of the INF, the last remaining arms control treaty is the 2010 New Start agreement limiting US and Russian strategic warheads, but that is due to expire in 2021 and Bolton has said it is unlikely to be extended.