ITV News Political Correspondent Carl Dinnen has the details of what happened - or didn't happen
The Ministry of Defence (MoD) has dismissed claims by Russian forces that warning shots were fired at a Royal Navy destroyer after it entered the country's territorial waters in the Black Sea.
The Russian Defence Ministry said in a statement, reported by the Russian Interfax news agency, that a border patrol boat fired warning shots at HMS Defender and a Su-24M warplane dropped four bombs close to the ship.
But the MoD rebutted the reports saying: "No warning shots have been fired at HMS Defender.
"The Royal Navy ship is conducting innocent passage through Ukrainian territorial waters in accordance with international law.
"We believe the Russians were undertaking a gunnery exercise in the Black Sea and provided the maritime community with prior-warning of their activity. "No shots were directed at HMS Defender and we do not recognise the claim that bombs were dropped in her path."
The British Ambassador has been summoned to the Russian Foreign Ministry because of the incident.
Defence Secretary Ben Wallace said: “This morning, HMS Defender carried out a routine transit from Odesa towards Georgia across the Black Sea.
"As is normal for this route, she entered an internationally recognised traffic separation corridor."
Mr Wallace said HMS Defender left the corridor "safely", adding "as is routine, Russian vessels shadowed her passage and she was made aware of training exercises in her wider vicinity."
Appearing later before the Commons Defence Committee, Mr Wallace said the crew of HMS Defender did hear "training noises" to the rear of the ship, but it was "beyond visual range".
He said the destroyer only varied course - away from Crimea - when a slower moving Russian vessel appeared in its path.
He said the Russians had previously made false claims to have "chased out" another British warship, HMS Dragon.
"These are the things that come an go with Russia. Disinformation, misinformation is something that we have seen regularly.
"We are not surprised by it," he said.
"We plan for it and we take all steps to make sure we are not escalatory or provocative.
"However we will not shy away from upholding international law and our rights on the sea."
Downing Street has said the Royal Navy destroyer HMS Defender was taking the “most direct” route from Ukraine to Georgia along an “internationally recognised travel corridor” and was not subject to warning shots fired by Russia.
The Prime Minister’s official spokesman said: “It’s incorrect to say either that it was fired upon or that the ship was in Russian waters. HMS Defender was taking the most direct and internationally recognised route between Ukraine and Georgia.
“As you know, the UK does not recognise Russia’s claim to Crimea and we continue to uphold the international consensus that Russia’s annexation of Crimea is illegal.”
He said the UK and other countries had been informed by Russia it was undertaking a “gunnery exercise” near to where HMS Defender was sailing.
“They provided us and others with prior warning of this activity,” the spokesman added.
The Russian statement had claimed: "The destroyer was warned in advance that weapons would be fired in case of a violation of the Russian state border.
"It disregarded the warning.
"As a result of joint actions of the Black Sea Fleet and the Border Service of the Russian Federal Security Service, HMS Defender left the territorial sea of the Russian Federation at 12.23pm."
HMS Defender - a Type 45 destroyer - is part of the UK Carrier Strike Group currently heading to the Indo-Pacific region.
However, it was announced earlier this month it would be temporarily breaking away from the group to carry out its "own set of missions" in the Black Sea.
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