Former French Economy Minister Arnaud Montebourg gestures as he delivers a speech during the 44th annual meeting of the French socialist party (PS) "La fete de la Rose", on August 21, 2016 in Frangy-en-Bresse. Arnaud Montebourg announced his candidacy for the 2017 presidential elections, on August 21, 2016 in Frangy-en-Bresse (Saône-et-Loire). He also said that his presidential project will be "socialist but not only" and that was impossible for him to support French President France Hollande. / AFP PHOTO / PHILIPPE DESMAZESPHILIPPE DESMAZES/AFP/Getty Images

Former French Economy Minister Arnaud Montebourg delivers a speech during the 44th annual meeting of the French socialist party (PS) "La fete de la Rose", on August 21, 2016 in Frangy-en-Bresse. Arnaud Montebourg announced his candidacy for the 2017 presidential elections, on August 21, 2016 in Frangy-en-Bresse (Saône-et-Loire). He also said that his presidential project will be "socialist but not only" and that was impossible for him to support French President France Hollande. / AFP PHOTO / PHILIPPE DESMAZESPHILIPPE DESMAZES/AFP/Getty Images

Former French Economy Minister Arnaud Montebourg delivers a speech during the 44th annual meeting of the French socialist party (PS) "La fete de la Rose", on August 21, 2016 in Frangy-en-Bresse. Arnaud Montebourg announced his candidacy for the 2017 presidential elections, on August 21, 2016 in Frangy-en-Bresse (Saône-et-Loire). He also said that his presidential project will be "socialist but not only" and that was impossible for him to support French President France Hollande. / AFP PHOTO / PHILIPPE DESMAZESPHILIPPE DESMAZES/AFP/Getty Images

Former French Economy Minister Arnaud Montebourg delivers a speech during the 44th annual meeting of the French socialist party (PS) "La fete de la Rose", on August 21, 2016 in Frangy-en-Bresse. Arnaud Montebourg announced his candidacy for the 2017 presidential elections, on August 21, 2016 in Frangy-en-Bresse (Saône-et-Loire). He also said that his presidential project will be "socialist but not only" and that was impossible for him to support French President France Hollande. / AFP PHOTO / PHILIPPE DESMAZESPHILIPPE DESMAZES/AFP/Getty Images

Former French Economy Minister Arnaud Montebourg delivers a speech during the 44th annual meeting of the French socialist party (PS) "La fete de la Rose", on August 21, 2016 in Frangy-en-Bresse. Arnaud Montebourg announced his candidacy for the 2017 presidential elections, on August 21, 2016 in Frangy-en-Bresse (Saône-et-Loire). He also said that his presidential project will be "socialist but not only" and that was impossible for him to support French President France Hollande. / AFP PHOTO / PHILIPPE DESMAZESPHILIPPE DESMAZES/AFP/Getty Images

Former French Economy Minister Arnaud Montebourg delivers a speech during the 44th annual meeting of the French socialist party (PS) "La fete de la Rose", on August 21, 2016 in Frangy-en-Bresse. Arnaud Montebourg announced his candidacy for the 2017 presidential elections, on August 21, 2016 in Frangy-en-Bresse (Saône-et-Loire). He also said that his presidential project will be "socialist but not only" and that was impossible for him to support French President France Hollande. / AFP PHOTO / PHILIPPE DESMAZESPHILIPPE DESMAZES/AFP/Getty Images

(FILES) This file photo taken on February 23, 2015 at Princeton University, New Jersey shows Arnaud Montebourg, former French socialist Minister of the Economy attending a discussion. Montebourg is to announce on August 21, 2016 that he will be candidate for the 2017 French presidential election. / AFP PHOTO / KENA BETANCURKENA BETANCUR/AFP/Getty Images

(FILES) This file photo taken on February 23, 2015 at Princeton University, New Jersey shows Arnaud Montebourg, former French socialist Minister of the Economy attending a discussion. Montebourg is to announce on August 21, 2016 that he will be candidate for the 2017 French presidential election. / AFP PHOTO / KENA BETANCURKENA BETANCUR/AFP/Getty Images