Liam Hemsworth: Kissing J-Law was gross

Actor Liam Hemsworth during an interview with Jimmy Fallon. Photo / Getty Images

For an actor or actress, having to kiss onscreen is often one of the trickiest things to do.

But for Liam Hemsworth it was one of the smelliest, too, when he had to smooch with co-star Jennifer Lawrence in The Hunger Games: Mocking Jay - Part 1.

"She's one of my best friends, I love her, but if we had a kissing scene she would make a point of eating garlic or tuna fish," the 24-year-old told The Tonight Show host Jimmy Fallon.

Liam Hemsworth and Jennifer Lawrence in Mockingjay Part 1.

"Any time I had to kiss Jennifer it was pretty uncomfortable," he said.

Jimmy also dug up the Australian actor's old school boy snap, bringing back his geeky past to haunt him.

After chatting about tearjerker films and celebrity crushes, 40-year-old host asked Liam what his most awkward moment was in high school.

The former Neighbours star explained he had a growth spurt as a teenager, which left him as a tall, and lanky student.

Keen to surprise his guest, Jimmy quickly whipped out an old school photo of the screen star, which featured curly blonde hair and freckles.

He playfully poked fun at the picture as Liam turned red with laughter, remarking that he thought he looked "pretty cool."

Jimmy Fallon and Liam Hemsworth on The Tonight Show with Jimmy Fallon. Photo / Getty Images

Jimmy and the Aussie later donned beer helmets to compete in the Hemsworth Cup, appropriately named after Liam and his brother Chris Hemsworth, who both beat Jimmy in scooter races.

The talk show host came out on top this time, scoring himself the somewhat coveted cup.

Liam was on the program to promote The Hunger Games: Mockingjay Part 1, which hits cinemas this week.

Watch Liam Hemsworth on The Tonight Show with Jimmy Fallon:

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- Daily Mail