Fans were critical in spite of the company's reasoning.
"The logical choice would have been, then, to remove a triangle or two from the bar," Leah Potter wrote on Facebook. "Surely you must be aware that a huge part of the excellent Toblerone experience is breaking off and sharing triangles of chocolate.
BBC News reported that similar sentiments were echoed by other customers, and that a spokeswoman refuted claims that the change was because of Brexit.
Toblerone and Mondelez maintain that despite impassioned fans disappointment in the new shape, there has been no change in taste.
"We appreciate the passion of the Toblerone fans around the world," Toblerone said in a statement on its Facebook page. "We will never compromise on taste nor our famous Swiss quality and can assure you that the Toblerone recipe hasn't changed."