He is the second person to resign from the council today.
The council is composed of prominent business leaders from American corporations.
Merck CEO Kenneth Frazier previously stepped down from the council due to President Donald Trump's response to the white nationalist demonstrations in Charlottesville, Va. over the weekend. Frazier criticized Trump for not immediately condemning the white nationalists.
Plank announced he was stepping down tonight, though he didn't give explicit reasons why. In his statement, he said his company "engages in innovation and sports, not politics."
Here is Plank's full release:
For a full list of who remains on the council, check Business Insider here.