And Sam Smith has since replied to say: "Apologies for the mix up @DLanceBlack I'll be sure to check out your films now x Belated Congrats on the Oscar x."
Dustin Lance Black has taken a cheeky swipe at Sam Smith, after the singer made an error in his Oscar acceptance speech.
Picking up the gong for 'Best Original Song' last night, Sam had mistakenly suggested he was the first openly gay person to win an Academy Award.
But he wasn't…
Cheekily responding to Sam's error, fellow Oscar winner Lance, who is engaged to Olympic diver Tom Daley, tweeted a link to a YouTube video of his own acceptance speech alongside the caption: "Hey @SamSmithWorld, if you have no idea who I am, it may be time to stop texting my fiancé. Here's a start."
Lance won 'Best Original Screenplay' for Milk in 2009.
Sam had said in his acceptance speech: "I read an article a few months ago by Sir Ian McKellen and he said no openly gay man had won an Oscar. If this is the case, I want to dedicate this to the LGBT community around the world. I stand here tonight as a proud gay man and I hope that we can all stand as equals one day."
But he was mistaken as other openly gay artists have one, including Dustin Lance Black and Sir Elton John, the latter of whom won 'Best Original Song' for 'Can You Feel The Love Tonight' from The Lion King.
Sam hasn't been on Twitter since his won. His last tweet was posted ahead of the ceremony, where he also performed, and spoke about how nervous he was feeling.
His win was for 'Writing On The Wall' from James Bond movie Spectre.
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