The Russian parliament has threatened to make Europe "vanish" if Western leaders deliver nuclear weapons to Ukraine.
Putin's top political ally Viacheslav Volodin, who is also head of the State Duma, cautioned such a move would provoke a nuclear conflict on the continent.
The threat comes after Poland's former foreign minister Radoslaw Sikorski reportedly called for the transfer of nukes to Ukraine's President Zelensky to bolster his defence.
No Western leaders have so far suggested arming Ukraine with nuclear weapons and it is unclear if Poland has plans to do so.
To which Volodin has now renounced, and as a key figure in Russian politics, his words are not to be taken lightly.
With such delegates, the Europeans will have much more serious problems than those they have already faced today, "refugees, record inflation, energy crisis", Volodin, the head of the State Duma, hit back on Telegram.
Sikorski provokes a nuclear conflict in the center of Europe. He does not think about the future of either Ukraine or Poland.
If his suggestions are enforced, these countries will vanish as well as Europe.
He needs to be assessed by a psychiatrist, pass the mandate and stay at home under supervision.
It is strictly because of people like Sikorski that it is crucial to liberate Ukraine not only from the Nazi ideology, but also to demilitarise it, ensuring the country's non-nuclear status.
Mr Sikorski told Ukrainian channel Espreso TV the Russian president had violated the Budapest Memorandum on Security Assurances of 1994, which pledges to respect Ukraine's territorial integrity, in exchange for Ukraine handing over it's nuclear arsenal to Russia.
He said this violation would justify the delivery of nuclear weapons from the West.
In a post on Twitter addressed to Volodin, Mr Sikorski said, You promised Ukraine to respect her borders in 1994 in return for her nukes.
You are now colonizing her and you threaten both Ukraine and NATO with your nukes. We just want you to know that if you use them, we have options too.