The German had been an outspoken critic of the management in recent days although he had denied any plans to end his tenure after just two years at the helm.
The former Stuttgart manager took Thailand to the final of the 2012 AFF Suzuki Cup where they were beaten by Singapore. But it appears that he was not happy with the level of involvement of certain executives in the day-to-day running of the national side.
He told the Nation over the weekend that he was astonished by the "disrespect and lack of professionalism" when the association announced a 20-man squad list for an upcoming friendly without his knowledge or supervision.
On Tuesday, the 63-year-old took to social media to reveal that he had come to a mutual agreement to cancel his contract that had one more year left to run.
"Yesterday [Monday] the FA of Thailand [Football Association of Thailand] and [I] cancelled the contract in mutual agreement. I am very sad about this development," he said from Berlin.
"I had a fantastic time with the kindest and good hearted players. I wish them all the best for the future.
"I will give you soon more information. Thank you for your support."
The Nation also reported that former national striker Kiatisuk Senamuang could be handed the reins given that he's already in charge of the squad that will participate in this year's Southeast Asian Games.
Image courtesy of WSG