French Prime Minister Sébastien Lecornu has reportedly resigned from his post hours after appointing his new cabinet. According to The Guardian, Lecornu appointed his ministers on October 5, 2025, after a week of consultation with other political parties. His reign as Prime Minister lasted only 27 days, making it the shortest term for a PM in modern France.As of this article, it is unclear why Lecornu, a close ally of President Macron, resigned within a month of his appointment. Élysée Palace announced the resignation in a short statement, which read:"Mr. Sebastien Lecornu has submitted the resignation of his Government to the President of the Republic, who has accepted it."Sébastien Lecornu was France's defence minister before he was made Prime Minister. He is France's fifth PM in the past two years and has been part of Emmanuel Macron's government since 2017.Emmanuel Macron had previously praised Sébastien Lecornu for his "practical approach"According to Radio France Internationale (RFI), Sébastien Lecornu, the grandson of a French Resistance fighter, grew up in Normandy. He studied law and entered politics at 19, becoming France's youngest parliamentary assistant. He got his political start in the rightwing party Union for a Popular Movement (UMP).Following this, Lecornu became the mayor of his hometown, Vernon. At age 29, he was the youngest person to be appointed president of the surrounding department of Eure. In 2017, he moved to Emmanuel Macron's centrist movement, where he was appointed Secretary of State to the Minister for the Ecological and Inclusive Transition.According to Time, he remained a pivotal part of Macron's government, helping the president during France's "Yellow Vests Movement." The movement, which began in 2018, was in protest of France's high cost of living and fuel tax. Following the movement, Macron launched the three-month national "grand debate" in 2019 to give citizens a platform to voice their concerns, which Sébastien Lecornu oversaw. Macron had praised Lecornu for his "practical approach" during the protest and subsequent debate.Emmanuel Macron and Sébastien Lecornu during a tribute to former European Commission President Jacques Delors In May 2022, Lecornu was appointed France's youngest defence minister and oversaw France's support for Ukraine in its conflict against Russia. He also helped boost France's military budget in light of the conflict.On September 9, 2025, he was announced as the new Prime Minister, following his predecessor, 74-year-old François Bayrou, who was reportedly ousted from his post after a vote of no confidence. Lecornu took to social media to issue his first statement following his appointment, writing:“The President of the Republic has entrusted me with the task of building a Government with a clear direction: the defense of our independence and our power, the service of the French people, and political and institutional stability for the unity of the country. I wish to thank him for the confidence he has shown me by appointing me Prime Minister."In another post, he added that he was willing to do "everything to succeed," writing:“I want to sincerely tell our compatriots that I understand their expectations and that I know the difficulties. We are at work, with humility, and we will do everything to succeed.”Not much is known about Sébastien Lecornu's personal life. According to the RFI, he preferred to keep a low public profile.insane moments in french politics @InsaneFrenchPolLINKPresident Macron has appointed Sébastien Lecornu as Prime Minister. Lecornu, a former LR member, had been serving as Armed Forces minister since May 2022. The next Government will be a Macronist-led government.French President Emmanuel Macron has yet to announce Sébastien Lecornu's successor as of this article.