‘This is not a bluff’

President Vladimir Putin yesterday called up 300,000 Russian military reservists, saying his promise to use all military means in Ukraine was "no bluff," and hinting that Moscow was prepared to use nuclear weapons.

His mobilisation call comes as Moscow-held regions of Ukraine prepare to hold annexation referendums this week, dramatically upping the stakes in the seven-month conflict by allowing Moscow to accuse Ukraine of attacking Russian territory.

A senior US official said Washington was taking Putin's "irresponsible" veiled threat to use nuclear weapons "seriously" and warned it could alter its "strategic posture" if need be.

US President Joe Biden tore into Putin yesterday as he addressed the United Nations, saying the Russian leader "shamelessly violated" the UN Charter when he invaded Ukraine.

Russian forces have attacked Ukrainian schools, railway stations and hospitals, part of Moscow's aim of "extinguishing Ukraine's right to exist as a state," Biden said.

Beijing, which so far has tacitly backed Moscow's intervention yesterday called for a "ceasefire through dialogue" after Putin's address.

Ukrainian President Volodymyr Zelensky, however, told German media he does not believe Russia will use nuclear weapons. "I don't believe that the world will allow him to use these weapons."

In an interview with Reuters, Nato Secretary-General Jens Stoltenberg denounced Putin's threat to use nuclear weapons as "dangerous and reckless rhetoric".

The moblisation plan demonstrated "that the war is not going according to his plans" and it was clear that the Russian president had made "a big miscalculation", Stoltenberg said.

In a pre-recorded address to the nation early yesterday, Putin accused the West of trying to "destroy" his country through its backing of Kyiv. Russia needed to support those in Ukraine who wanted to "determine their own future", he said.

The Russian leader announced a partial military mobilisation, with Defence Minister Sergei Shoigu telling state television that some 300,000 reservists would be called up.

"When the territorial integrity of our country is threatened, we will certainly use all the means at our disposal to protect Russia and our people. This is not a bluff," Putin said.

An EU spokesman said the mobilisation was proof Putin wanted an escalation of the conflict, not peace.

The Russian leader said that through its support for Ukraine the West was trying to "weaken, divide and ultimately destroy our country". Shoigu said Moscow was "fighting not so much Ukraine as the collective West" in Ukraine.

In the wake of their announcements flights to neighbouring ex-Soviet countries were booked up for days to come, airline data showed, in what appeared to be a rush to quit the country, reports AFP.

The sudden flurry of moves by Moscow this week came with Russian forces in Ukraine facing their biggest challenge since the start of the conflict.

In a rare admission of military losses from Moscow, Shoigu said 5,937 Russian soldiers had died in Ukraine since the launch of the military intervention in February.

As Putin made his announcement, Ukrainian nuclear operator Energoatom yesterday accused Russia of again striking the Zaporizhzhia atomic power plant in southern Ukraine.

In the battlefield, residents were clearing rubble and broken glass from a nine-storey apartment block hit by an overnight missile strike in the eastern Ukrainian city of Kharkiv.