Since France has the largest Muslim population in Western Europe (almost 10% of the French population, and estimated at close to 6 million) Muslims claimed there was not enough room in the mosques for adherents to pray, hence congregating on the streets. To accomodate the 1,000 or so that have been hauling their prayer mats outdoors, the state will rent to several Paris mosques an empty fire brigade barracks capable of holding 2,000, at least until a new mosque is built.
Not that there's a dearth of mosques in France. As of 2010, there was an estimated 2,000 mosques, although many are supposedly small. But the leader of the Grande Mosque of Paris would like that number to change- and, of course, built with state funds, which poses a problem in a secular state. I guess he figured that since there are approximately 40,000 churches, and Muslims account for 10% (and growing) of the French populace, 4,000 would be a goodly number.
One French writer of algerian descent, Nabila Ramdani, balks at the French law that banned state funding of any religious establishment back in 1905. According to Ramdani,
The difference is: needs will increase exponentially; whereas Christians, Jews and others would not have as great a need for new space. Frankly, in a secular nation, no government monies should be spent on the building of any religious edifice. Let followers fund their own buildings. That would solve that issue. If a country wants to remain secular, than it needs to stay out of religion.
"Other faiths, including Christians and Jews, all infringe the 1905 law, as they receive funding from the state. So there's no reason whatsoever why Muslims shouldn't enjoy the same kind of funding, even if the money is passed off as cultural money. They should have the same opportunities as other faiths."