Joe Biden warns Putin against nuclear attack on Ukraine

US President Joe Biden has warned his Russian counterpart Vladimir Putin against using chemical or tactical nuclear weapons in the wake of serious losses in Moscow's war in Ukraine.

"Don't. Don't. Don't," he told the US TV show "60 Minutes" in an interview to be broadcast Sunday.

"You would change the face of war unlike anything since World War II," Biden said.

Asked what the US response would be, Biden said such an action would be "consequential."

"They will become more of a pariah in the world than they have ever been," the president said. "And depending on the extent of what they do will determine what response would occur."

Tactical nuclear weapons can be used over short distances and are generally smaller in power, although modern tactical warheads are still several times more powerful than the ones used by the US during the WWII in Hiroshima and Nagasaki.

UK: Russia increased targeting civilian infrastructure

The British Defense Ministry said in its regular intelligence update that Russia had increased targeting civilian infrastructure in the last week, "even where it probably perceives no immediate military effect."

The report noted the strikes on a dam on the Inhulets River at Kryvyi Rih in southern Ukraine, one of the country's largest urban areas. The strike caused flooding and subsequent damage that Ukrainian authorities are still repairing. 

"As it faces setbacks on the front lines, Russia has likely extended the locations it is prepared to strike in an attempt to directly undermine the morale of the Ukrainian people and government," the ministry added.

Zelenskyy accuses Russia of Nazi practices

Ukrainian President Volodymyr Zelenskyy said investigators had found evidence of "10 torture chambers" in recaptured towns in the northeastern Kharkiv region.

"Torture was a widespread practice in the occupied territories. That's what the Nazis did — this is what [the Russians] do," Zelenskyy said in a video address late on Saturday.

"They will answer in the same way —  both on the battlefield and in courtrooms," he vowed.

Earlier this week, Zelenskyy said more than 400 bodies were discovered in a mass grave in the town of Izium in Kharkiv after Ukrainian forces recaptured it as part of a counteroffensive operation.

Australia won't ban Russian tourists

Australian Defense Minister Richard Marles said the country was not considering a ban on Russian tourist visas as part of its sanctions on Moscow.

Speaking with Australian broadcaster ABC, Marles said Canberra's sanctions on Moscow were aimed at the Russian government, "not the Russian people themselves."

Australia has sanctioned hundreds of Russian individuals and institutions linked to Russia's banking sector and sovereign debt since the beginning of the war in Ukraine.

Canberra has also banned some exports to Russia and supplied military and humanitarian supplies to Ukraine.

"We will be looking at how we can provide that ongoing support," Marles said, adding that Australia was "one of the largest non-NATO military support of Ukraine."