Russia is preparing to test a nuclear missile which is so advanced it could get past Nato defences and destroy a large slice of Europe within seconds of launching.
The RS-28 Sarmat missile, dubbed Satan 2 by Nato, has a top speed of seven kilometres (4.3 miles) per second and has been designed to outfox anti-missile shield systems.
The Kremlin's new intercontinental ballistic missile will be ready for field trials this summer, according to the Russian news network Zvezda, which is owned by Russia's ministry of defence.
The report comes only days after Russia showed off its military might in a Victory Day parade which was reminiscent of the Cold War days under the Soviet Union.
The Sarmat missile could deliver a warhead of 40 megatons - 2,000 times as powerful as the atom bombs dropped on Hiroshima and Nagasaki in 1945.
Zvezda reported the missile could destroy an area the size of France or Texas.
It is expected to have a range of 10,000 km (6,213 miles), which would allow Moscow to attack London and other European cities as well as reaching cities on America's west and east coasts.
Igor Sutyagin, an expert in Russian nuclear capability at the Royal United Services Institute in London, told Mail Online: 'The SS-18 is more than 30 years old. It is past its sell-by date.
'So even if you had the warmest relations in the world with Nato you would want to update your missiles. But (President) Putin of course is happy for it to be portrayed as an aggressive move. He wants to stress his unpredictability and his importance.'
Dr Sutyagin points out that the SS-18 missiles which the Russians currently rely on were designed in 1988 during the Soviet Union and were built at a factory in Dnipropetrovsk, in what is know the Ukraine.
He said the Russians cannot totally rely on the Ukraine-based maintenance engineers and he said Sarmat were designed and built by Russians at the Khrunichev plant just outside Moscow.
The Sarmat has been in development since 2009 and is scheduled to start replacing the old ICBMs in 2018.
Dr Sutyagin they would be no match for Nato systems like Aegis Ashore, the controversial missile defence shield which the US is deploying to Romania.
He said: 'Not only are they too fast but they have got rid of the predictable flight path. It manouevres all the way so it is terribly difficult for any missile defence system to shoot it down.'
The Russian Defence Ministry plans to put the Sarmat into service in late 2018 and remove the last SS-18 by 2020.