Actress Kate Beckinsale has been photographed kissing her new 21-year-old boyfriend.

The Underworld star was snapped making out with Matt Rife in West Hollywood after a date night at trendy nightclub Villa Lounge on Tuesday (20Jun17).

Sources tell news show Entertainment Tonight that Kate's relationship with the muscular young comic is for real, insisting the the lovebirds are "officially boyfriend and girlfriend".

"They quickly started flirting, went on their first date and it's continued since," one insider details.

Kate, 43, met Matt through a mutual friend and apparently her closest loved ones approve of the romance, despite the massive age difference.

"Everyone in Kate’s circle loves Matt and are so supportive of this relationship," the source adds. "He really is the sweetest guy and makes her so happy! Her entire family thinks he is the nicest and most lovely person. He is very mature for his age and is a great guy."

Rife, who has appeared on Nick Cannon's TV comedy series Wild 'N Out, appears to have teased his relationship with the sexy British beauty on social media. In a now-deleted post on his Instagram account, the fit emerging talent shared a silly photo of himself posing in front of a senior citizens center and added the caption: "Age is just a number. Find someone you love, and take their breath away... even if that means putting a kink in their oxygen tank cord. #LifeAlertTypeOfLove".

Beckinsale split from her director ex Len Wiseman in 2015 after 11 years of marriage and their divorce was finalized last year (16). She also has an 18-year-old daughter from her previous relationship with Welsh actor Michael Sheen.