The 'I, Tonya' star – who is one of the favorites in the best actress for a lead category tonight – is known to have a wicked sense of humor.
Australian beauty Robbie, 27, confessed that she made the call after being spurred on by Cara Delevingne while the duo were filming 'Suicide Squad' back in 2016.
She said: "Cara knows Harry and while we were filming Suicide Squad she was like, 'Let's prank-call him'.
"I said, 'We can't prank-call royalty', but anyway we did — and he was so cool with it.
"Prince Harry is so nice - England literally has the coolest royalty in the world."
The actress spoke previously about Harry's upcoming nuptials to Meghan Markle on The Kyle & Jackie O Show back in January.
Co-host Jackie 'O' Henderson asked the Gold Coast-born beauty to confirm if she was friends with him.
"I wouldn't say we're close,' she admitted.
"We see each other every so often at a party here or there, but not close friends."
When asked if she would be attending the royal wedding, she wasn't hopeful.
"No, definitely not that close!" she insisted.
But who knows? if she scoops the Oscar tonight then she might be heading to the wedding on May 19 in Windsor, England.
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