The pair reportedly began dating after the Want To Want Me singer collaborated with the girl group on their upcoming single Secret Love Song, which they performed live for the first time at the Capital FM Jingle Bell Ball in London on Saturday (05Dec15).
Jade's bandmate Jesy Nelson let the news slip, telling Britain's The Sun newspaper, "She's got someone on the go. His name starts with J... then a D."
"He's very hot. It's early days," Jade adds.
Jesy then described Jason's flirty behaviour with Jade onstage during the Jingle Bell Ball at the O2 Arena, saying, "He's so lovely, really, really sweet... He gave Jade a little wink when we introduced him on stage. There's four of us but he looked to Jade and gave her a wink."
Jesy continued discussing the romance by comparing Jason to Nick Jonas, another Jingle Bell Ball performer, who has been 'liking' Jade's pictures and sending her private messages on Instagram.com, adding, "Jason's a bit more manly. Nick's a nice boy but Jason, I feel like he'd look after her. She's only little," and Jade joked, "Yeah, he can pick me up!"
Jade previously confessed to having a crush on Nick, telling a radio station in November (15), "Hopefully one day I can see him and see what happens... I really like him."
Jason split from singer Jordin Sparks in 2014 after three years of dating, and he recently insisted the pressure to get married was a large factor in the split, saying,"I think true love can never be broken, so I don't think that I have found true love... There was a lot of arguing and stuff like that... When you stop having more good times than bad times, it's time to call it quits. It becomes something that is unhealthy."