Russia could use nuclear weapons if Putin suspects an “existential threat”.

The Kremlin’s main mouthpiece has refused to rule out nuclear war – and readily warns that President Vladimir Putin could use nuclear weapons if he perceives an “existential threat”.

Dmitry Peskov was repeated pressed on CNN on Tuesday about Russia’s nuclear arsenal being placed on high alert, which interviewer Christiane Amanpour told him had “terrified the world”.

“President Putin wants the world to hear and understand our concerns,” the Kremlin spokesman said when asked if Putin would “use” the nuclear option.

“We have a concept of internal security and it’s public, you can read all the reasons for using nuclear weapons,” he said, urging it again.

“Well, if it’s an existential threat to our country, then [the nuclear arsenal] can be used according to our concept,” he warned.

While Putin’s key spokesman did not specifically address what would be considered an “existential threat,” he repeated unsubstantiated claims that Ukraine was attempting to build its own nuclear arsenal.

“We tried for a couple of decades to take our concerns out into the world – to Europe, to the United States – but nobody would listen to us,” the Kremlin spokesman complained.

“And before it’s too late, it was a decision to start – to launch a special operation, a military operation, to get rid of the anti-Russia created next to our borders,” he said.

To Amanpour’s apparent amazement, Peskov insisted that modern Ukraine “was created by Western countries” just to be “anti-Russian.”

He also claimed the Kremlin had “very strong reasons to believe and very strong evidence” that the US had developed “biolaboratory programs” in Ukraine.

“That’s the reality we face,” he said.

Just days after his invasion last month, Putin ordered Russia’s nuclear forces put on “increased combat duty” over its unsubstantiated claims about NATO threats.

UN Secretary-General Antonio Guterres later said: “The prospect of nuclear conflict, once unthinkable, is now again within the realm of possibility.”

During his CNN interview on Tuesday, Peskov dismissed rumors that the “military special operation” in Ukraine had suffered embarrassing setbacks and delays.

“It will be carried out strictly according to the plans and with the purposes set out beforehand,” he said.

He also denied that Russia had attacked civilians, despite overwhelming eyewitness accounts and Ukraine’s claims that at least 121 children were among the dead.

“We will hurt Nazis, not ordinary people and civilians. Targeting civilians for our military is forbidden,” he said, dismissing reports to the contrary as “propaganda.”