Putin warns of 'lightning response' to intervention in Ukraine

Speaking to lawmakers, Putin said that "if anyone sets out to intervene in the current events from the outside and creates unacceptable threats for us that are strategic in nature, they should know that our response... will be lightning-fast".

The Russian leader said that the military would not hesitate to use the most modern weaponry.

"We have all the tools for this, that no one else can boast of having. We won't boast about it: we'll use them, if needed. And I want everyone to know that," Putin said.

"We have already taken all the decisions on this."

Putin has frequently touted Russia's development of modern weaponry, including hypersonic missiles and the new Sarmat intercontinental ballistic missile that was successfully tested earlier this month.