The Swiss stock exchange (SWX) has relieved Reto Francioni of his duties as chairman with immediate effect.
The SWX said the decision was connected with Francioni's nomination to the top position at its German counterpart, Deutsche Börse.
Francioni was last week recommended to replace Werner Seifert, who resigned as chief executive of the German stock exchange in May.
In a statement on Wednesday, the SWX group said it had "taken note" of Francioni's nomination.
"The board of directors extends its best wishes to Reto Francioni for his election and future tasks, and would like to express its sincere gratitude for his devotion and the services he has rendered on behalf of SWX."
It said that "in the interest of proper procedure" the board had relieved its chairman of all his obligations with immediate effect.
A report in Wednesday's Tages-Anzeiger newspaper had speculated that Francioni would be suspended from his position because of a possible conflict of interest resulting from his likely move to one of SWX's main competitors.
Until a successor is elected, the board is to be headed by its current vice chairman, Jacques de Saussure.
"We very much look forward to collaborating with him [Francioni] in his new function," de Saussure was quoted as saying.
In its statement, SWX said it would examine Francioni's recommendation that a former head of the Zurich bourse, Antoinette Hunziker-Ebneter, should succeed him. But it said it would also consider other potential candidates for the job.
Speaking last week, Francioni described Hunziker-Ebneter as being "ideally qualified" for the position.
Francioni, who is 50, is expected to take over at the Frankfurt bourse on January 1.
swissinfo with agencies
Deutsche Börse has been searching for a new chief executive since May, following the resignation of Werner Seifert.
Reto Francioni, aged 50, knows both the Swiss and German bourses well. He was on the board of Deutsche Börse from 1993 to 2000 and has been at the SWX since 2002.
The supervisory board of the Deutsche Börse is to decide on Francioni's nomination on October 10.