Sir Nicholas Soames said Alexander Yakovenko's claims were rubbish
Sir Nicholas Soames and other allies of Foreign Secretary Boris Johnson hit out at the Kremlin's top diplomat in the UK for warning British relations with Russia are "at an all time low".
The Second World War prime minister's grandson and MP said Alexander Yakovenko's assertions were "rubbish" misinformation from a "wretched" Kremlin.
He said: "The wretched Ambassador probably wasn't even born during the Cold War — it was much worse when I was soldiering in the 1970s.
"I think it is hyperbole and I think everyone just need to be very aware of what the Russians are trying to do which is upset the apple cart."
Following a British deployment of 800 Nato troops to the Estonian border with Russia on Sunday Mr Yakovenko, said: "We deplore that deployment for it raises tensions in Europe along the border between Nato and Russia.
"Russia doesn't pose any threat to Estonia nor any other Nato member-state.
"That is why all the talk of territorial defence sounds provocative, and with [the] changing nature of war, outright ridiculous."
Alexander Yakovenko said the UK and Russia were on the verge of a Cold War
When asked if this was the worst point in UK-Russia relations, Mr Yakovenko, said: "Yes, it is."
Sir Nicholas, a former Army officer, called for "clear minds and a cool head and just recognise we seek better relations with Russia, but they have to understand how the rules work and they don't have a clear run".
Russian politicians have ramped up their criticism of the West, with Mikhail Gorbachev, the Soviet Union's last leader, yesterday warning Russia and the West are heading towards another Cold War era.
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He said: "The rhetoric used by politicians and senior military commanders is becoming more and more belligerent.
"All the indications of a Cold War are there.
"Troops are being moved into Europe, including heavy equipment such as tanks and armoured cars. It was not so long ago that Nato troops and Russian troops were stationed quite far away from each other.
"They now stand nose-to-nose. One gets the feeling that the world is getting ready for a new war."
Sir Nicholas Soames (r) is Winston Churchill's grandson
British Naval ships had to escort Russian ships out of British waters this weekend
Britain's politicians have been quick to dismiss their threats as simple rhetoric.
A friend of Boris Johnson said: "Russia could end all of these issues now if it wanted. It's not us on the wrong side of the argument."
A Whitehall source, added: "Russia has the chance to improve its relations with the international community by stopping its support for Assad the butcher, ending its illegal annexation of Crimea and respecting the sovereignty of Ukraine."
Dr Julian Lewis, chairman of the powerful Commons Defence Committee, said Mr Yakovenko failed to take a "sufficiently long view of the history of our relationship".
He said: "I can think of times when it's been a lot worse — even in my own lifetime."
He added the "big difference from the old confrontations is that it used to be much worse because of the atrocious Soviet, Communist and Marxist ideology — which at least isn't a factor these days".
Dr Lewis predicted the Ambassador would regret his criticism.
He said: "I think probably on reflection he may feel that his remarks were overstated in an admittedly unsatisfactory situation."
Talking about the British deployment, Former Foreign Secretary Sir Malcolm Rifkind, added: "If the Russians don't like it they must change their behaviour.
"That's Nato policy – that's not just the UK – that's America, Germany, Britain and a number of other countries and that is a direct consequences of his own Government's attempts to destabilise the Baltic states in recent years."