Irish singer Niall jumped into the frame while Liam was cuddling up to girlfriend Sophia Smith for a selfie.
(Liam and Niall? Lucky Sophia!)
Liam uploaded the fun shot to Instagram on Saturday (31 May) with the caption: "Nice romantic moment when..."
We're pretty sure Sophia didn't mind a double 1D cuddle!
Liam's photo was favourited more than 500,000 times, with comments including: "Haha, nice romantic picture, then you see Niall!" Another said: "Lol, Niall, third wheeling!"
"That would have been a cute picture though," said another. "Now, it's hilarious. I love the faces!"
Liam's photo is firm proof that he and Sophia are back together. (If they ever split at all.) A series of cryptic messages posted to Twitter by Liam recently had prompted speculation of a break-up, but that was put to rest last week when he and Sophia where seen walking hand-in-hand in Birmingham.
Then, yesterday, the singer was pictured leaving his Manchester hotel with Sophia, following One Direction's concert in the city.
And, just to erase any doubt at all, he also uploaded a screenshot to Instagram on Sunday showing a newspaper article declaring Liam and Sophia to be the most popular baby names in Wyoming, USA. "How strange. Ha," he wrote.
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