Former French Economy Minister Arnaud Montebourg (C) poses for a picture with supporters 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 (C) 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 (R) sings the French national anthem after his 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 (C) 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 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 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 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 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