Liam Payne and new girlfriend Sophia Smith seem like they are deeply in love....or at least they can't keep their hands off each other. Watch the two in action in a video below.

One Direction's Liam Payne and his new beau Sophia Smith stepped out last night in London to celebrate his 20^th birthday.

Payne may have been the star of the party...but he couldn't keep his eyes off Sophia.

Liam only went public as dating Sophia earlier this month...but it seems like the their relationship is moving fast. Very, very fast.

Payne couldn't keep his hands off Sophia while walking between the car and the club. The two cuddled each other protectively before they swarmed through a sea of paparazzi on their way into Liam's birthday party at the trendy Funky Buddah.

Liam put his arm around Sophia protectively to shield her-even though the paparazzi were there for him.

It seems One Direction's Payne is deeply smitten with his girlfriend Sophia Smith.

Payne previously dated Danielle Peazer, his backup dancer, for two and a half years...but his relationship with Sophia seems more affectionate.

The two went to St. Peter's Collegiate in Wolverhampton together-and she seems to be adjusting to being on the 1D scene.

Liam Payne and Sophia Smith spent the entire day together, stopping by the set of the new One Direction music video.

Earlier this month, Payne revealed he was dating Smith when a reporter asked him if he had a girlfriend. "Yes yes I do. She's sitting right over there. It's not been long," he said, pointing at Sophia.

WATCH VIDEO of the Sophia Smith and Liam Payne in action below. What do you think from the body language? How's their chemistry?