The royal who is famed for his bumbling gaffes is said to have asked the talented actress if she knew how to fix a DVD player.
'Prince Philip began discussing his DVD, which he said was broken,' says a source. 'He said: There's a cord sticking out of the back of the machine. Might you tell me where it goes?".'
Cate, 38, had to explain to the 86-year-old Duke of Edinburgh that she's an actress and not a technical expert.
A spokesman for Prince Philip played down the incident.
'The Duke of Edinburgh meets so many people when he is escorting the Queen on engagements,' he tells the Daily Mail. 'These are often film stars, actors and actresses.
'I cannot recall an occasion recently when he might have met Miss Blanchett but we do not always get guest lists for every engagement or social function."'
Heavily pregnant Cate is nominated for Best Actress (Elizabeth: The Golden Age) and Best Supporting Actress (I'm Not There) at this year's Oscars, to be held on 24 February.
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