Russia-Ukraine latest: Putin orders nuclear deterrence forces on high alert
Nato chief: Putin's nuclear rhetoric is 'dangerous' and irresponsible.
The United States responded by saying Putin was escalating the war in a "totally unacceptable" way.

Nato chief: Putin's nuclear rhetoric is 'dangerous' and irresponsible.
The United States responded by saying Putin was escalating the war in a "totally unacceptable" way.
Russia says the main cause of the deadly incident on board a submersible which killed 14 crew on Monday was a fire in the battery compartment.
Gunmen have attacked a convoy of trucks carrying uranium fuel to a nuclear power plant near the Brazilian city of Rio de Janeiro, police say.
President Donald Trump and Kim Jong Un failed to strike a nuclear deal Thursday, abruptly ending their Vietnam summit hours early and leaving the fate of North Korea's nuclear weapons up in the air.
US Congresswoman Tulsi Gabbard said that "we face a greater risk of nuclear catastrophe now than ever before in history"
The Trump administration is to reinstate all US sanctions on Iran removed under the 2015 nuclear deal.
South Korea’s spy agency has observed preparations by North Korea for international inspections at several of its nuclear and missile test sites, the Yonhap news agency said on Wednesday, citing a South Korean lawmaker.
President Donald Trump said Washington will exit the Cold-War era treaty that eliminated a class of nuclear weapons due to Russian violations, triggering a warning of retaliatory measures from Moscow.
Russia has condemned US plans to withdraw from a Cold War-era nuclear weapons treaty and threatened to retaliate for a "very dangerous step".