Sam Smith is said to have become romantically involved with his boyfriend while they both partied at Taylor Swift's 25th birthday celebrations.

The 22-year-old singer revealed earlier this month that he was dating one of the extras from the music video for his single 'Like I Can' and it's now been suggested their relationship first took a romantic turn at his pal Taylor's 25th birthday bash.

Sam Smith reportedly got together with his boyfriend at Taylor Swift's birthday party.

The London based star is reported by the New York Post newspaper's PageSix to have gotten close to the wannabe actor while partying at the 'Shake It Off' hitmaker's New York home.

The new couple celebrated Taylor's birthday along with US stars including Justin Timberlake, Beyonce, Jay Z, Selena Gomez and Victoria's Secret model Karlie Kloss at her apartment in Tribeca.

Sam hinted at the romance at the time by posting an image on his Instagram account of himself with the arm of a mystery man around his shoulders.

The 'I'm Not The Only One' crooner captioned the snap with lyrics from fellow British singer Duffy's 2008 hit single 'Mercy', writing: "'I don't know what this is, but you got me good' (sic)".

Meanwhile, despite admitting his new beau is very "sweet", Sam insists he will "never" be happy.

He said previously: "The reason I do what I do is because I'm an artist who is always going to be blue about something.

"It's just the way I am - I'm an emotional person."

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