The Pentagon said that Russia could not use nuclear weapons, although the US president warned of the risk of the end of the world.

It is necessary to clarify that we have not seen any reason to adjust our strategic nuclear status as well as no signs about Russia being preparing to use nuclear weapons, spokesman for the Ministry.

Pentagon Secretary Pentrick Ryder on October 6 told reporters that the agency has not received any information may cause them to change the nuclear state related to Russia.

Pentagon spokesman Todd Breasseseae at a meeting in Washington capital on April 12.

The Pentagon's statement came after US President Joe Biden warned that the world was first facing the risk of the end of the nuclear day since the Cold War.

President Putin said that Russia could use all available tools, including weapons with different levels of destruction, to protect territorial integrity.

Russian Deputy Foreign Minister Sergey Ryabkov on September 23 explained that Putin's warning, confirmed that Russia did not threaten anyone with nuclear weapons, instead warn the West that their intervention in Ukraine

However, Western and Ukrainian officials all think that the warning must be considered seriously from Russia, and expressed concerns about the risk of small tactical nuclear weapons that can be used on

Russia is the largest nuclear power in the world according to the number of nuclear warheads that it owns.

Moscow is concerned about the possibility of using tactical nuclear weapons in Ukraine, but this is also a big risk scenario for Russia itself.

When Ukraine tensions escalate with new developments, Mr. Biden's headache is calculating how to react if Russian nuclear warnings come true.