Admiral Sir Tony Radakin said: We know that Russia acknowledges that it's lost nearly 500 people, to put that into a context that's nearly 500 soldiers in one week.

"That is more than the UK lost in Afghanistan over 20-years, Ukraine claimes nearly 10,000 casualties and we don't know if that is true but we do know that some of the lead elements of Russian forces have been decimated by the Ukrainian response.

BBC Journalist said: "How worried are you that President Putin could use nuclear weapons?"

BBC News Putin nuclear warfare

Admiral Sir Tony Radakin added: "So I think we've got to be very cautious about President Putin's threats.

"We are part of the world's largest military alliance, we have our own nuclear deterrent, we've got to retain calmness and responsibility so that we don't just react rashly to whatever is the latest, frankly at times bizarre or ridiculous comment form President Putin.

"So we are prepared, we are professional armed forces, we will approach this conflict with that level of professionalism and responsibility that you would expect.

Reference:Daily express:  Ebun Hargrave