In 1984, Margaret Thatcher met Mikhail Gorbachev, who looked set to become the leader of the Soviet Union. The Iron Lady afterwards said he seemed like an individual with whom Britain “can do business”. But Mrs Thatcher had a more disparaging view of Russia’s current leader, Vladimir Putin.

In 2000, Moscow’s nuclear submarine Kursk sank in the Barents Sea, killing all 118 crew, and the UK’s first female prime minister launched a scathing attack on the Kremlin chief after observing his response to the incident. Mrs Thatcher felt the loss of British military personnel extremely deeply, as shown by her writing of personal letters to the families of all 255 of those killed during the Falklands War.

Following the submarine tragedy 18 years later, she said in a speech: “Now we have the new Mr Putin. I looked at the pictures of Mr Putin, trying to look for a trace of humanity.

“I should, within a few weeks, have known better.

“Because you know what happened? They had the terrible tragedy of the submarine going down.

“But it was very interesting what happened.

“If ever there is a calamity in the west, the whole of the armed forces will go. They will take everything there immediately.

“The policians immediately will get together and say, ‘What help do we want? They can have anything we can give. If we haven’t got the help, we’ll get it from someone else.’

“There would be anxiety, because what mattered was not the submarine, but the lives of those in.

Mrs Thatcher added: “The interesting was that the new leader of [Russia] didn’t act quickly… he didn’t try to mobilise everyone else.

“We didnt know whether we could help.

“We were all ready to go and help and send some of the small submarines we that we had for just such an occasion.

“That, my friends, was very, very revealing indeed.

“They still do not value human life in the same way that we do.