Christian have stepped down as coach of Algeria over two years before the end of his contract.
The Algerian Football Federation announced his departure on their official website, saying that they had “ended his contract amicably at his request”.
The Frenchman had told his bosses of his wish to leave on Thursday, according to local reports, on the plane flying back from an African Cup of Nations match against Ethiopia.
After three wins and a draw, Algeria are top of their qualifying group for the 2017 African Cup of Nations, needing just one win from their remaining games against Seychelles away on June 3 and Lesotho at home on September 2 to guarantee qualification.
The former France international was appointed in 2014.