Halal meat, or meat slaughtered in line with Muslim tradition, is at the centre of a political controversy.

Quick - a fast-food French restaurant chain - is testing out a new niche market, withdrawing all pork products from the menu and serving only halal meat in some of its branches.

Experts say that with more than 5 million French Muslims who are potential customers, Quick is targeting a booming market: the $7.5bn halal business.

But the mayor of Roubaix, a French town near the northern city of Lille, has launched a law suit against the food chain, arguing that it constituted "discrimination" against non-Muslims.

And Marine Le Pen, the vice-president of the far-right National Front party,  has warned of "Islamisation".

Al Jazeera's Estelle Youssouffa reports from Paris.