Britain's young minister for energy and climate change, Ed Miliband, had come to Russia to talk about global warming. Little did he know he would end up meeting a long-lost member of his family.
It came in the middle of a phone-in programme on the popular Moscow radio station "Ekho Moskvy".
As the fresh-faced Mr Miliband prepared to answer questions on CO2 emissions and melting permafrost, the voice of an elderly woman came on the line.
"I am Sofia Davidovna Miliband, I am your relative; I am the only one left."
As the British minister looked on bemused, the host of the show cut her off - clearly worried she was a hoaxer.
But it was no hoax.
The British ambassador and dozens of invited guests (and the BBC) were left stranded at an embassy reception as Mr Miliband raced off to meet his long-lost kin.
It turns out that Sofia Davidovna Miliband is an 86-year-old academic.
She was once a leading expert on Iran at the Moscow School of Oriental Studies.
I've always slightly wondered about her ever since I was a kid, it was amazing for me to come face to face with her
After much translation and a call to his mother in the UK, the British minister - whose brother David, is the UK's foreign secretary - worked out that his great-great grandfather was the brother of Sofia's grandfather.
Both of them had been born in the Jewish quarter of Warsaw in Poland.
Ed Miliband's grandfather fled Poland in the 1920s and ended up in Belgium. He fled again ahead of Hitler's invading army and made it to Britain on forged papers with his son, Ed and David Miliband's father.
Unknown to them another part of the Miliband clan had come east to Moscow.
Sofia Davidovna reportedly told him she was delighted.
She has no children and thought she was the last of the Milibands.
Little did she know that in faraway England there are not one, but two of them in the British cabinet.
Mr Miliband told BBC Radio 4's PM programme his relative was "an amazing woman".
"I did sort of vaguely know when I was a boy about her existence. The way I know about it, if you look on a library computer her name pops up.
"I've always slightly wondered about her ever since I was a kid, it was amazing for me to come face to face with her."
On meeting her, he said: "I think she was much less interested in what David or I do than in making the family connection and realising she wasn't the last Miliband around and that there was a branch of the family in Britain."
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