Two wives of French jihadis captured in Iraq are facing the death penalty, which France formally abolished in 1981.
And lawyers representing the women penned a letter calling on the French president to fight for the wives as they await trial.
William Bourdon, Vincent Brengarth and Martin Pradel wrote: “France has repeatedly called for the worldwide abolition of the death penalty, no matter how grave the crime.”
The lawyers called on Mr Macron to respect their clients’ fundamental right to a “fair trial”, adding they had “serious doubts about the fairness of the trial procedure” in Iraq.
However, the French government said earlier this month all jihadis arrested in Kurdish-held areas of Syria or Iraq should face local justice so long as they could be guaranteed a fair trial.
The call for Mr Macron to come to the women’s defence came days after an Iraqi court sentenced to death a German woman of Moroccan descent for joining ISIS.
The 50-year-old, known only as Lamia K, was captured by Iraqi forces during the battle for Mosul last year and is the first foreign woman to be handed the death penalty in Iraq for her role in ISIS’ savage regime.
The two French women detained in Iraq were also captured after the fall of Mosul.
The first woman, Djamila B., 28, fled to Iraq with her jihadi husband in 2015.
Now reportedly a widow, she is currently being held in an Iraqi prison along with her young daughter.
The second, 27-year-old Melina B., also left France in 2015, and was with her four children when she was arrested.
The three eldest were repatriated back to France in December, while the youngest, who is just a few months old, stayed in Iraq with his mother.
Earlier this month Mr Bourdon and Mr Pradel and two other lawyers announced that their Syria-based clients – the wives and children of ISIS militants captured by Kurdish forces – had filed a legal complaint against the French government for refusing to repatriate them.
The lawyers said– unlike Iraq – Syrian Kurdistan is not a legally recognised state and that their clients were being held in “unauthorised detention”.
Some 30 French jihadists, both men and women, are currently being held in Iraq and Syria, according to French security sources.