"Having supported Eric Zemmour in the presidential election, I decided to join the Reconquete movement and take an active part in it. Therefore, I am glad to announce my appointment as executive vice president," Marechal wrote on social media.
In January, Marechal said she would back Le Pen's main rival on the right-wing end of the spectrum, Eric Zemmour, or whoever was in a better position to take on incumbent Emmanuel Macron. Le Pen later said it was difficult for her to process her niece's refusal to back her in the French presidential election, describing Marechal's decision as "brutal."
Marion Marechal, 32, is the granddaughter of Jean-Marie Le Pen, the founder of the National Front, which Marine renamed to National Rally after taking over in 2012. Marechal served on the National Assembly for the southeastern Vaucluse department from 2012 to 2017.
On Sunday, France held the first round of the presidential election. Incumbent President Emmanuel Macron received 27.84% of the vote, followed by Le Pen with 23.15%, which means they will face one another in a second round on April 24.
Zemmour came in fourth with 7.07% of the votes and has urged his supporters to vote for Le Pen in the runoff.