By Samia Nakhoul, Guy Faulconbridge and Vladimir Soldatkin

ST PETERSBURG, Russia (Reuters) -President Vladimir Putin said on Friday Russia had no need to use nuclear weapons to secure victory in Ukraine, the Kremlin’s strongest signal to date that Europe’s deadliest conflict since World War Two will not escalate into a nuclear war.

Since Putin ordered troops into Ukraine in February 2022, he has said on several occasions that Russia would use such weapons if necessary to defend itself – comments the West says are nuclear sabre-rattling.

Asked at the plenary session of the St Petersburg International Economic Forum by moderator Sergei Karaganov, an influential Russian analyst, if Russia should hold a “nuclear pistol to the temple” of the West over Ukraine, Putin said he did not see the conditions for using such weapons.

“The use is possible in an exceptional case – in the event of a threat to the sovereignty and territorial integrity of the country. I don’t think that such a case has come. There is no such need,” Putin said.

Moscow considers Crimea – which it seized from Ukraine in 2014 – and four other Ukrainian regions now as integral parts of its own territory, raising the possibility of a nuclear strike if Kyiv appeared poised to retake them.

Ukraine has stepped up drone and missile attacks on Russian targets, including in Crimea, and has vowed to drive all Russian forces from its territory.

Putin said he did not rule out changes to Russia’s nuclear doctrine, which sets out the conditions under which such weapons could be used.

He also said that if necessary Russia could test a nuclear weapon, though he saw no need to do so at the present time.

The public debate about nuclear strikes on a stage at Russia’s premier economic forum appeared to be a Kremlin attempt to reduce nuclear fears just as the Ukraine war escalates towards what both Russian and U.S. diplomats say is its most dangerous phase yet.

Russia and the United States hold nearly 90% of the world’s nuclear weapons.

NUCLEAR WAR?

Last year Karaganov proposed a limited nuclear strike on a NATO member in Europe to force the West to back off in the conflict over Ukraine and thus avert World War Three.

On Friday Karaganov invoked the Biblical story of how God destroyed the cities of Sodom and Gomorrah for their wickedness as he pressed Putin on whether Russia should escalate in Ukraine to teach the West “a lesson”.

Putin said he prayed that the world would never witness a nuclear confrontation, adding: “And we don’t have that need. Because our armed forces are not just gaining experience, they are increasing their effectiveness.”

Russian troops are advancing along the front line in Ukraine, Putin said, adding they had taken 880 square km of territory since the start of the year, including 47 villages and towns.

Putin said Russia had increased ammunition production by more than 20 times and was outproducing Ukraine and the West on a whole series of measures.

Russia’s published 2020 nuclear doctrine sets out the conditions under which a Russian president would consider using a nuclear weapon: broadly as a response to an attack using nuclear or other weapons of mass destruction, or to the use of conventional weapons against Russia “when the very existence of the state is put under threat”.

“But this doctrine is a living tool and we are carefully watching what is happening in the world around us and do not exclude making some changes to this doctrine. This is also related to the testing of nuclear weapons.”

“If necessary, we will conduct tests. So far, there is no need for this either…,” he added.

U.S. President Joe Biden has relaxed some restrictions on Ukraine’s use of U.S. weaponry inside Russia, prompting warnings from Moscow of a potentially dangerous escalation in the conflict, now well into its third year.

Putin said on Wednesday he could deploy conventional missiles within striking distance of the United States and its European allies if they allowed Ukraine to strike deeper into Russia with long-range Western weapons.

Biden, speaking in France on Friday where he has been attending celebrations of the 80th anniversary of the D-Day landings, reaffirmed the United States’ commitment to support Ukraine and again drew a comparison between the fight against Nazi Germany and the threats posed by dictators today.

(Additional reporting by Reuters; Editing by Kevin Liffey and Gareth Jones)

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