PARIS (Reuters) - A call to prayer goes up from a loudspeaker perched on the hood of a car, and all at once hundreds of Muslim worshippers touch their foreheads to the ground, forming a sea of backs down the road.
The scene is taking place not in downtown Cairo, but on a busy market street in northern Paris, a short walk from the Sacre Coeur basilica. To locals, it's old news: some have been praying on the street, rain or shine, for decades.
But for Marine Le Pen -- tipped to take over from her father this weekend as leader of the far-right National Front party -- it is proof that Muslims are taking over France and becoming an occupying force, according to remarks she made last month.
Her comments caused a furore as she seized on the street prayers to drive home the idea that Islam is threatening the values of a secular country where anxiety over the role of Muslims in society has deepened in the past few years.
More than two thirds of French and German people now consider the integration of Muslims into their societies a failure, pollster IFOP said in a survey published on Jan. 5. In France, where Islam is the second-largest religion after Catholicism, 42 percent saw it as a threat to national identity.
"This has become a key political issue," said Frederic Dabi, IFOP's head of research. "Street prayers and the perceived growing influence of Islam are seen as impinging on French values of secularism, communal living."
Controversy over the street prayers has translated into growing confidence within the National Front, some 15 months before a presidential election likely to see a battle for votes between the far right and Sarkozy's centre-right UMP party.
National Front founder Jean-Marie Le Pen has said he expects the party to outdo its electoral performance in 2002, when it knocked out the mainstream Socialist candidate in the first round of voting, but then lost to Jacques Chirac.
"These fears hang mostly on symbols: minarets in Switzerland, the niqab (full-face veil) in France, even the halal Quick menu," Dabi said, referring to a fast-food chain which recently opened a range of halal-only restaurants in France and Belgium. "The far right is playing on these fears."
Le Pen's comments seem to be taking hold. A poll published by TNS Sofres this week, showed that support for National Front ideas has grown by 12 percentage points over the past year.
Back on the market road, Friday prayers come to an end as quickly as they begin, with hundreds of worshippers packing up their mats and heading back to work.
Many told Reuters that given the choice, they would avoid the cold and rain and pray indoors. The problem is that their warehouse-turned-prayer site, an unofficial mosque called al Fath, is too small to accommodate them all.
"It's cold and filthy. Do you think we would be out here praying if we had the choice? The whole neighbourhood comes and prays in the street because there is not enough room inside, that's all," said Mohammed Delmi, 62.
Such scenes are replicated at a dozen sites across France where worshippers kneel outside because prayer rooms are too full, according to a report by the centre-left daily Liberation.
"There are simply not enough of them," said Hakim El Karoui, head of the Islamic Culture Institute, which advises the City of Paris on faith issues. "It's no wonder there is an overflow."
The problem has grown along with the country's Muslim population, which the French Council of Islamic Faith estimates at between 5-7 million, or 8 percent of the population -- a larger community than in any other European nation.
Campaigners in favour of building new mosques said they faced two major difficulties, starting with financing: mosques in France must be funded privately due to restrictions against using public money for religious purposes.
The second, pricklier issue is the public, which has grown increasingly intolerant of Islamic symbols. Research by pollster IFOP shows that support for building mosques fell to 20 percent in 2009 from 31 percent in 2000.
"We are walking on egg shells here," said Moussa Niambele, head of a group seeking new prayer space near the al Fath mosque. "There is the minaret issue in Switzerland and they do not want to import such problems to France."
In Paris, where the Muslim population is denser than elsewhere in France, there is only one official mosque, La Grande Mosquee de Paris, located by a park on the posh Left Bank, far away from immigrant-heavy neighbourhoods.
El Karoui said the problem had grown more acute since the closure of a large mosque in northern Paris two years ago forced more Muslims to pray in converted garages or vacant lots.
A project to build two new prayer spaces which would be called "cultural" and "faith" centres lacks 5.9 million euros of private funding and building would not start before 2012.
Worshippers were sceptical about the timetable.
"You know, we have been praying on this street for years, long before Marine Le Pen made her remarks," said one man.
"I am not going to throw away my raincoat quite yet."
(Editing by Catherine Bremer and Sonya Hepinstall)