Kim Kardashian West and Paris Hilton. Picture: Instagram

Paris Hilton has recruited Kim Kardashian West to join her for a "secret project".

The duo met up together to film scenes for a new music video for Paris' new song 'Best Friend's Ass' with Dimitri Vegas and Like Mike.

Taking to Instagram, Paris captioned a video of the pair: "#SecretProject with @KimKardashian ... I can't stop looking at my #BestFriendsAss (sic)"

Paris and Kim have been friends for a long time, with the latter acting as Paris' stylist at one point.

Speaking about their bond and asked if she looks back at the days when they were close friends fondly, Paris said: "Yeah, we had so much fun. She's a great wing woman, someone to hang out with, fun to be around, beautiful."

The blonde beauty also slammed claims she helped to boost Kim's career and insists her former best pal is "killing it".

She shared: "I'm happy for her. We had so much fun travelling the world, and I have so many fun memories and I'm just so proud of the woman she has become today.

"Some people do say that [I helped her], but that's not something I've ever said. She's just killing it and she's so happy, so I'm happy for her."

Paris Hilton believes that she and Kim share the same work ethic and that's why they've both been successful.

She said: "Kim Kardashian always had a great work ethic like me. I'm very determined in life. Being successful really fulfils me. I work hard. I'm a good person with a good heart. That's why I've been in this business for so long, and that's why my product lines do so well."