Kate Beckinsale is reportedly "totally smitten" with her rumoured beau Matt Rife.

Kate Beckinsale

Kate Beckinsale

The 'Love & Friendship' actress is believed to be dating the 21-year-old comedian, and sources have now said the pair are "happy" that they no longer have to sneak around and hide their burgeoning romance from the world.

A source claimed: "Kate and Matt are totally smitten with each other. They're happy that the news is out that they are together and they don't have to sneak around anymore."

And 43-year-old Kate - who has 18-year-old daughter Lily with her former partner Michael Sheen - isn't concerned about the 22 year age gap between herself and Matt either, as the funny man is thought to be "very mature for his age".

The insider added: "Kate and Matt are having fun. The age difference isn't really an issue. Matt is very mature for his age and wise beyond his years ... [he] has dated girls in the past but this seems the most serious."

The pair are believed to have enjoyed a romantic date at the Sherman Oaks Galleria in Sherman Oaks, California, over the weekend, where an eyewitness claimed they were "super affectionate" towards one another.

An onlooker told 'Entertainment Tonight': "Kate was really happy. She looked completely smitten with Matt. Kate was always touching him the entire time they were waiting for the car at the valet. They were also holding each other as they rode on the escalator. Kate was kissing him. They were super affectionate."

News of Kate and Matt's romance broke earlier this month after they met through "mutual friends", though it is unclear as of yet exactly how long the pair have been seeing one another.

A source said at the time: "[Kate and Matt] met through a mutual friend. [They are] officially boyfriend and girlfriend. They quickly started flirting, went on their first date and it's continued since."

And according to the insider, Kate's family and friends have already put the seal of approval on the hunk, as he's the "sweetest guy".

The source added: "Everyone in Kate's circle loves Matt and are so supportive of this relationship. 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."

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