The English singer was on "Watch What Happens Live" when a caller asked if she ever thought about collaborating with The Biebs, a question that comes after the two were on a Snapchat video together.
"We're just friends," the "Fifty Shades Darker" star said, ending any speculation that they are romantic.
As for the video, Rita said, "You know what it was, we're just musicians vibing. We had a few drinks, just musicians jamming out. but you never know. I have so much love and respect for him, so."
As she thought about collaborating with Justin, she added, "It would be a good idea. Let's put it out, the energy."
On Feb. 6, a video posted to Rita's Snapchat showed her singing "All My Life" by K-Ci and JoJo while Justin played piano.
"Turn it around," Justin can be heard saying while he tickled the ivories.
In 2014, Rita confessed that she had a thing for the "Sorry" singer. During an appearance on 4Music, she was asked if she "fancied" Justin.
"Who doesn't?," she said. "I like how he's evolved, he's growing up, he's doing his thing. I like his stance and how he carries himself."
At the time, Rita's relationship with deejay Calvin Harris was collapsing. TMZ said then that The Biebs played a factor in the split.
"Word got back to Calvin, Justin and Rita got touchy feely with each other while they were in the recording studio together over the last few months," the report said. "Calvin heard they were very affectionate – she would sit on his lap [and] he would rub her back."