He will continue to serve as a non-executive director of Freud's and will oversee the transition of client responsibilities. His current clients include Sony Pictures, Warner Music, MySpace, Random House and Working Title.
Thykier joined Freud in 1992, working closely chairman and founder Matthew Freud and chief executive Nick Wiszowaty to build the media and entertainment area of the PR and event company's business.
Freud's Nicola Howson, Kate Lee and Patrick Keegan will continue to run the media, film and entertainment divisions and will take responsibility for Thykier's clients.
Vaughn, who produced Lock, Stock and Two Smoking Barrels and Snatch before directing Layer Cake and the forthcoming fantasy epic Stardust, said: 'I have worked with Kris on every picture since Lock, Stock. Over the years we have become an incredibly close working unit and I trust him completely. He has an innate understanding of consumers matched with unparalleled experience in marketing and media. I hope and believe that as partners we will be able to build a truly significant company in the UK, producing quality movies with international commercial appeal.'
Thykier added: 'I have spent the majority of my professional life at Freud Communications and this has been a very tough decision. The last 15 years has been an unforgettable journey and one that I will never forget. However, I have long held the desire to move into film production and the opportunity to build a new company with Matthew Vaughn is too exciting to miss. I look forward to continuing my involvement with Freud's as a non-executive director and in future as a client.'