LONDON - European leaders have urged the United States not to abandon a landmark Cold War-era agreement prohibiting the U.S. and Russia from possessing ground-launched tactical nuclear missiles; but, they have tempered their reaction to President Donald Trump’s threat to do so by supporting his call for the Kremlin to be more transparent about its new missiles.

The U.S. leader’s announcement of his plan to withdraw from the Reagan-era Intermediate-Range Nuclear Forces (INF) Treaty of 1987 has prompted a flurry of disapproval in Europe with predictions that quitting the pact will trigger an arms race and return Europe to the danger of a hair-trigger nuclear exchange.

Europeans Criticize Trump Plan to Quit Arms Pact

On Tuesday, U.S. National Security Adviser John Bolton told reporters in Moscow that Washington hasn’t yet supplied Russia with official notification that it intends to withdraw from the historic arms treaty, but said such a move would be coming “in due course.”

Europeans Criticize Trump Plan to Quit Arms Pact

Bolton has long been a critic of the treaty, citing Russian violations of the pact in the form of the development and deployment of a missile the Russians designate as the 9M729. Russian officials deny the 9M729 is an intermediate-range cruise missile, but the Obama administration, too, had worried about the class and range of the missile, telling Congress of its concerns in 2011. The weapon has been described as non-compliant with the terms of the treaty.

Europeans Criticize Trump Plan to Quit Arms Pact

In early 2017, a senior U.S. military officer said that Russia had begun deploying the missile. Russia denies the missile is non-compliant.

Of the major European powers, only Britain has offered support, with the country’s defense secretary, Gavin Williamson, accusing Moscow of making a “mockery” of the INF treaty, an agreement that eased Cold War tensions. Britain stands “absolutely resolute” with the U.S., Williamson told the British media, “in hammering home a clear message that Russia needs to respect the treaty obligation that it signed.”

“We of course want to see this treaty continue to stand but it does require two parties to be committed to it and at the moment you have one party that is ignoring it,” Williamson said.

But while other European leaders are also calling on Russia to be more transparent about new missile developments, they say the INF treaty, which has kept nuclear missiles out of Europe for almost three decades, shouldn’t be abandoned.

“The INF contributed to the end of the Cold War and constitutes a pillar of European security architecture since it entered into force 30 years ago,” a spokeswoman for European Union foreign policy chief Federica Mogherini said in a statement. She added, “The world doesn’t need a new arms race that would benefit no one and, on the contrary, would bring even more instability.”

France’s Foreign Ministry argues great importance should be attributed to conventional and nuclear arms control agreements. “We call on all the parties to avoid any hasty unilateral decisions, which would be regrettable,” the ministry said in a statement. And Germany has advised against the scrapping of the treaty, saying it will be placed in a tough spot by the U.S. abandonment.

German officials say they will seek NATO's help to keep the INF treaty alive and use all diplomatic means to do so. But they also stress the Kremlin bears much of the blame for the U.S. plan to abandon the pact by saying the alliance has to be ready to take action to force Moscow to comply with its INF obligations.

German Foreign Minister Heiko Maas Tuesday told a German newspaper, “The American frustration is not unfounded. But that should not result in throwing the baby out with the bath water.” Maas said there is understandable anxiety about Russia's failure to address allegations it is violating the treaty.

Then-U.S. President Ronald Reagan and then-Soviet leader Mikhail Gorbachev signed the INF treaty in 1987. It bans either the U.S. or Russia from possessing, producing or test-firing ground-launched nuclear cruise missiles with a range of between 480 and 5,500 kilometers. Trump has accused Moscow of violating the treaty “for many years” and warned Russia and China, which is not a signatory to the agreement, to cease their development of ground-launched tactical nuclear missiles, otherwise the U.S. will restart its own program.