When the BBC's Steve Rosenberg interviewed Mikhail Gorbachev this week he certainly didn't expect it to end in a sing song. Steve explains what happened:

The interview was over and Mr Gorbachev was showing us the grand piano in the corner of the room. 'Can any of you play?' he asked. I nodded. 'Then, please, play something," he replied.

I sat down and played the Russian classic 'Moscow Nights' - and Mr Gorbachev began to sing. That was followed by 'Dark is the Night' and 'The Misty Morning' - a song he said was a favourite of his late wife.

'Raisa liked my singing' he smiled. It was a slightly surreal, but rather special moment which I think shows the warm human side of the man who ended the Cold War.