British astronaut Tim Peake feared being left in space if the West's relationship with Russia deteriorated, a Foreign Office minister said.
But Tobias Ellwood told members of Parliament he had received assurances from Russian President Vladimir Putin that Peake will not be abandoned on the International Space Station.
The Conservative Party politician, who said he is a friend of Peake, raised the issue with Putin during the 2015 European Games in Baku, Azerbaijan.
A Russian Soyuz rocket took the astronaut into space in December. He is spending six months on board the space station.
Speaking during a Westminster Hall debate on Anglo-Russian relations, Ellwood said: "I had the opportunity to meet President Putin at the Baku Azerbaijan Games last year and wasn't quite expecting to see him, I have to say.
"But I did say to him that a friend of mine had cause to use Russian transport and was a bit concerned about international developments — the East and West — and he might get stuck at the end of his destination and not be able to get back.
"That friend of mine was called Tim Peake, he was using a Soyuz space capsule to get himself up to the International Space Station and didn't want to be abandoned up there.
"Mr. Putin grabbed my arm and said, 'Mr. Ellwood, tell Mr. Peake we will not abandon him.
"And that gives you an indication to say that it is possible to isolate some of these enormous concerns that we have, the sanctions that take place, that allow us to work on the international stage to tackle some of these areas, but also culturally and professionally and indeed from an industrial perspective, commercial perspective, to be able to continue these relationships."
Thursday, Peake spoke to school children at Ashfield Primary School in Otley, West Yorkshire, via satellite.
He told the youngsters how he has grown a little more than an inch during his time on the International Space Station.
He also revealed the existence of a secret drawer of sweets and sugary treats on the station.
Peake has been busy during his time in space. Last month, he ran the London Marathon on a treadmill on the space station.