Martin Winterkorn, Volkswagen Group chief executive, has resigned amid the NOx emissions bypassing scandal.
In a statement, he said: "I am shocked by the events of the past few days. Above all, I am stunned that misconduct on such a scale was possible in the Volkswagen Group.
"As CEO I accept responsibility for the irregularities that have been found in diesel engines and have therefore requested the Supervisory Board to agree on terminating my function as CEO of the Volkswagen Group.
"I am doing this in the interests of the company even though I am not aware of any wrong doing on my part.
"Volkswagen needs a fresh start – also in terms of personnel. I am clearing the way for this fresh start with my resignation.
"I have always been driven by my desire to serve this company, especially our customers and employees. Volkswagen has been, is and will always be my life.
"The process of clarification and transparency must continue. This is the only way to win back trust. I am convinced that the Volkswagen Group and its team will overcome this grave crisis."