Only after Mr Osborne finished his presentation did the US president realise his mistake.
Someone who was present at the briefing told The Sun: "It got really cringe-worthy by the end.”
According to the FT (£), Mr Obama is reported to have explained himself, saying: “I’m sorry, man. I must have confused you with my favourite R&B singer.”
Unlike the Chancellor, Jeffrey Osborne has had an illustrious music career with five gold and platinum solo albums. He is best known for the 1982 hit On The Wings of Love:
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The shadow chancellor appeared to differ from his leader, who had been initially reluctant to blame the Kremlin for the ex-spy attack.
The Foreign Secretary said the Kremlin's tit-for-tat expulsion of 23 British diplomats would only impact Vladimir Putin's compatriots.
Sunday will be bitterly cold with snow for most.