Russia has withdrawn its request to refuel warships destined for Syria in Spain amid mounting pressure on the Spanish government to block the stop.
Warships led by the aircraft carrier Admiral Kuznetsov were expected to take on fuel and supplies at the port of Ceuta after passing through the Straits of Gibraltar.
But Defense Secretary Michael Fallon warned that Britain would be “extremely concerned” if a Nato member assisted a carrier group that ended up bombing Syrian civilians.
Speaking in Brussels, where Nato defence ministers are meeting, Mr Fallon said: “We would be extremely concerned if any Nato member started to assist a Russian carrier group that ended up in the eastern Mediterranean bombing Syrian civilians.
“On the contrary, Nato should be sticking together and reassuring its members and that’s one of the reasons we are deploying Typhoons to the Black Sea region to provide exactly that kind of reassurance and solidarity.
“Nato needs to stick together.”
Russia’s embassy in Madrid later said the federation had withdrawn its refuelling request.
It comes after Royal Navy vessels last week monitored Russian warships as they moved through the English Channel.
The fleet was shadowed by the Navy as it passed through the Dover Strait – one of the busiest seaways in the world.
Nato said the prospect of Russia’s only aircraft carrier heading to the region did not “inspire confidence” that Moscow is seeking a political solution to the Syrian crisis.
More than 60 Russian naval vessels have refuelled and resupplied in Spanish ports in recent years, according to the SNP.
But Prime Minister Theresa May sidestepped calls to explicitly demand that Spain rejected Russian refuelling requests.
She told MPs: “Of course, on the high seas they are able to travel as they wish, although of course when they went through the English Channel they were accompanied by Royal Navy vessels as they went through.
“What we have seen, sadly, is that the Russians are already able to unleash attacks on innocent civilians in Syria.
“What matters is that we put pressure on Russia to do what everybody agrees is the only way that we are going to resolve this issue, which is to ensure that we have a political transition in Syria, and that’s where we should focus our attention.”
Amnesty International UK said there should be “no question” of countries assisting Russian warships.
Its Syria campaign manager, Kristyan Benedict, said: “There should be no question of other countries refuelling these vessels or in any other way assisting Russia’s warships as they sail toward Syria.
“The Russian military’s record of attacks on schools, hospitals and civilian homes in Aleppo and elsewhere in Syria is notorious. Third-party countries must avoid becoming complicit in any future Russian attacks on Syria carried out in the eastern Mediterranean.”