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The pair were seen sitting side-by-side on the the curb outside Chelsea Handler's comedy show on Saturday night — but quickly separated when they were spotted by photographers.
Selena, 21, was wearing a low-cut back maxi dress and back cardigan, while English actor Orlando, 37, was casually dressed in layered jackets, jeans and a T-shirt.
It's not the first time the two have spent time together. Back in March, they both appeared as guests at WE Day, a conference aimed to inspire young people, and the Come and Get It singer shared a photo of them backstage, alongside Seth Rogen.
It's not the first time they have hung out: Selena Gomez and Orlando Bloom backstage at WE Day
But it's thought their romantic reunion came to a swift end — at the same time that Selena 'unfollowed' Justin, Kendall and Kylie Jenner on Instagram.
"Selena is convinced something has gone on between Justin and Kylie," a source told the Sun.
"At Coachella they (Justin and Selena) looked to be back on track. Selena was hanging out with Kylie too and they were behaving like best friends… Then she heard stuff about Justin and Kylie and felt totally betrayed. She went berserk and called it all off again."
Orlando, meanwhile, remains on good terms with his ex-wife Miranda Kerr. The couple, who have a three-year-old son Flynn together, announced their split in October after three years of marriage.