Sam Smith has jokingly compared his boyfriend Brandon Flynn to The Little Mermaid villain Ursula in unflattering photos of the couple kissing.

The Stay With Me hitmaker was photographed passionately locking lips with actor Brandon during a night out in London late last month (Feb18), but Sam has since revealed the pair purposefully staged the over-the-top public make-out session after finding themselves surrounded by the paparazzi.

"It was a joke - as a joke we were attacking each other," the British musician told BBC Radio 1. "We were just waiting outside the shop while my sister got cigarettes. I was just joking. I was literally licking his eyeballs!"

The steamy images quickly went viral, and Sam admits he now cringes whenever he sees them.

"(The photos are) horrendous," he laughed. "I'm going to have to do something crazy to top it."

Poking fun at Brandon's expression in the pictures, Sam made reference to a well-known scene in Disney's animated film The Little Mermaid.

"He looks like Ursula sucking the voice out of Ariel," the singer quipped. "It's so embarrassing."

Sam isn't the only one who appears to regret playing up the smooch for the cameras. After the shots hit headlines, 13 Reasons Why star Brandon commented on a social media post featuring a meme of the raunchy kiss, adding a crying face emoji to indicate his unhappiness.

The couple was first linked in October (17), when Sam and Brandon were pictured kissing and holding hands in New York.

At the time, Sam confirmed he was in a relationship, but avoided naming his boyfriend in media interviews while promoting his latest album, The Thrill of It All.

"I'm not (single), which is crazy," he told talk show host Ellen DeGeneres. "It's weird bringing out an album and not being single. Because when I brought (out) In the Lonely Hour I was so lonely. But now I'm singing songs about another guy, I'm quite happy, so it's quite weird."

The stars finally went public with their romance in December (17), when Brandon made their relationship social media official, sharing a snap of the couple wearing turquoise travel neck pillows with novelty unicorn hoods attached.

In the caption, he revealed he was in Sam's homeland by writing, "Rare sighting in London," followed by two unicorn emojis.