It is understood that Hachette's chairman, Kevin Hand, called Kirkman into his office yesterday and the decision was reached.
A spokeswoman for the publisher said that "the situation just wasn't working out for him".
Kirkman has more than 20 years' experience in the media industry, particularly in the agency sector. He switched to the client side last year from Carat where he was press director, responsible for billings in excess of £250m. He started his career at Saatchi & Saatchi.
While a replacement is being found, the ad department is to be led by commercial directors, Cath Ware and Clare Dempster.
In March this year, Kirkman oversaw a restructure at the publisher that saw Ware and Dempster promoted. The publisher also created a sales support department that will bring research, ad marketing and IT systems into one department.
In an official statement, Hand said: "I would like to thank Tim for his work with us over the eight months he has been here. "
Hand said that a successor would be appointed shortly.
Hachette Filipacchi publishes titles including Red, Elle, Elle Decoration, B, Sugar, Elle Girl, TV Hits!, Inside Soap and All About Soap.
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