Darmanin told a question and answer session with the Voix du Nord newspaper that the three from northern France -- who had been sentenced to death in Iraq, then jailed for life -- would be returned.

"Yes, as is the case for a lot of French detainees in the world, in Iran and elsewhere," he said.

"Nationals must finish their prison sentence in France. I believe that we cannot ask Algeria, Morocco or the United States to take back their nationals... and refuse to bring back French citizens held abroad," he added.

Darmanin gave no details about how any repatriations in total would take place. The foreign ministry did not immediately comment.

Lawyer Maria Dose said her client Djamila Boutoutaou, who received a 20-year prison sentence in Iraq in April 2018, was "seriously ill and must be repatriated urgently".

Another lawyer Richard Sedillot, who represents three French nationals sentenced in Iraq, said transfering prisoners would make their "reintegration" into French society easier.

"Their presence in France also allows French magistrates to question them," he argued, adding that the trio were at the centre of other investigations.

Sedillot said the three were being held in "disgraceful conditions" and an investigating magistrate was probing suspected torture against six French nationals held in Baghdad.