Their characters were mortal enemies ever since arriving at Hogwarts for their first year of witchcraft and wizardry.
However it seems that off-screen Matthew Lewis and Tom Felton are good pals, as during their reunion they took to Instagram to share a jokey snap, the DailyMail reports.
Harry Potter star Matt, who played the lovable Neville Longbottom in the hit franchise, posted a picture of himself with Tom who was holding up a piece of Slytherin merchandise.
Matt, who starred as cowardly bully Draco Malfoy, slung his arm around his friend in the shot which had been captioned: 'Take your Slytherin paws off me, you damn dirty ape!'
The take on the quote, coined in the 1968 version of Planet Of The Apes, sent Harry Potter fans wild as they rejoiced at the reunion.
One excited fan penned in the comments section 'this is everything', while another added 'living for this friendship though!'.
Tom posted a very similar image on his own Instagram page, with the caption 'See how close he was to converting.... @mattdavelewis #gryffindork', making light of their house rivalry.
The star was recently spotted sharing a smooch with a mystery blonde in LA ahead of his meet up with his co-star Matt.
Tom, who is known for sustaining a private romance life, previously dated co-star Jade Olivia for seven years.
The 31-year-old beauty took her on-screen romance with the star off-screen as she played the wife of Tom's character Draco in Harry Potter and the Deathly Hallows: Part 2 in 2011.
While the pair enjoying an array of romantic getaways and appearing on glitzy red carpet, Tom and Jade called it quits in early 2016.
Tom rose to fame after appearing as Harry Potter's in-school nemesis in all eight films, based on the globally popular books by J.K. Rowling about The Boy Who Lived.
Carving a successful career in acting from the franchise, the Brit has since gone on to star in Rise of The Planet of The Apes and A United Kingdom.