French junior minister for Digital Economy Axelle Lemaire arrives at the Elysee presidential Palace in Paris for the first weekly cabinet meeting following the summer holidays. Maverick left-winger Montebourg is the third former minister from President Francois Hollande's Socialist government to declare his intention to stand as a candidate after former ecology minister Cecile Duflot and Benoit Hamon, who once headed the education ministry. / AFP PHOTO / STEPHANE DE SAKUTINSTEPHANE DE SAKUTIN/AFP/Getty Images

French Economy and Industry minister Emmanuel Macron arrives at the Elysee presidential Palace in Paris for the first weekly cabinet meeting following the summer holidays. Maverick left-winger Montebourg is the third former minister from President Francois Hollande's Socialist government to declare his intention to stand as a candidate after former ecology minister Cecile Duflot and Benoit Hamon, who once headed the education ministry. / AFP PHOTO / STEPHANE DE SAKUTINSTEPHANE DE SAKUTIN/AFP/Getty Images

People take the stairs at the central business district in Singapore August 8, 2016. REUTERS/Edgar Su

BRISTOL, TN - AUGUST 21: Michael McDowell, driver of the #95 Thrivent Financial Chevrolet, and Carl Edwards, driver of the #19 Stanley Toyota, leads a pack of cars during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Brian Lawdermilk/Getty Images)

Former French Economy Minister Arnaud Montebourg (C), flanked by former French Culture Minister Aurelie Filippetti (2nd L) waits prior to deliver 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), flanked by former French Culture Minister Aurelie Filippetti (L) waits prior to deliver 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 (C), flanked by former French Culture Minister Aurelie Filippetti (2nd L) waits prior to deliver 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