Aleksey Zhuravlyov, 59, boasted about the terrifying threat which he claims would eradicate Finland, which is poised to join NATO, within 10 seconds.
The deputy chairman of the parliament’s defence committee made the wild remarks in response to the Western unity against Russia.
It comes as senior officials appear to be concerned at Putin’s lack of military progress in Ukraine.
Asked whether Russia would now rebase nuclear weapons onto its border with Finland, Zhuravlyov said: “What for? We don’t need to.
“We can hit with a Sarmat [known in the West as Satan-2] from Siberia, and even reach the UK.
“And if we strike from Kaliningrad, the hypersonic’s reaching time is 200 seconds – so go ahead, guys.”
He said Russia would massively strengthen its military forces on its western flank and said the US would do “everything possible to make World War III happen.”
The chairman added: “They will try not to lead to nuclear strikes, but they will try to draw the whole of Europe into a conflict with Russia, inflame the situation in Asia, [and] set fire to as many countries as possible .”
He told Ura news outlet that Russia could “certainly” strike first with nuclear weapons and claimed that St Petersburg – Putin’s birthplace – could be NATO’s first target in a war with Russia.
“This is the main goal [in this direction]. This is beyond any doubt,” he said.
Russia’s new ‘big beast’ hypersonic Sarmat is a 208-ton 15,880mph intercontinental ballistic missile.
Putin has said the weapon is “unstoppable” by the West with “no analogues in the world for a long time to come”.
Recently warmonger TV anchor Dmitry Kiselyov, 68, told his Russian TV audience that Britain should be flooded twice with Putin’s most advanced nuclear weapons.
He proposed the use of Satan-2 to wipe England from the map.
The Kinzhal hypersonic missile has been deployed with conventional warheads in the Ukraine war – but is also nuclear-capable.
Russia separately urged its people not to travel to Britain, and vowed to block UK citizens seeking to enter its country.
Moscow has blamed Britain for acting as a Western coordinator and cheerleader of the tough NATO response to Putin’s invasion of Ukraine.
In a statement, the Russian foreign ministry said: “Taking into account the extremely unfriendly course of the UK towards our country, in order to avoid financial losses and other possible problems, we recommend that Russian citizens refrain, if possible, from traveling to the UK and trying to obtain British visas.
“Until the situation is normalised, we will act in the same way with respect to the British.”
The statement said: “Recently, the Russian Foreign Ministry has received numerous complaints from Russian citizens that it has become virtually impossible or extremely difficult for them to obtain a visa to the UK.
“We are talking not only about tourists, but also about Russians working in the United Kingdom on contracts, as well as those who want to visit relatives or reunite with their families.
“According to the explanations of the British, at present the UK Visa Service allegedly gives priority to the processing of visa applications for Ukrainian refugees.
“For this reason, consideration of applications for British visas of Russians is significantly delayed.”
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