Islamic mosques are being built more often in France than Roman Catholic churches, and there now are more practising Muslims in the country than practising Catholics.

Nearly 150 new mosques currently are under construction in France, home to the biggest Muslim community in Europe. The mosque-building projects are at various stages of completion, according to Mohammed Moussaoui, the president of the Muslim Council of France (CFCM), who provided the data in an August 2 interview with the French radio station RTL.

The total number of mosques in France has already doubled to more than 2,000 during just the past ten years, according to a research report "Constructing Mosques: The Governance of Islam in France and the Netherlands." France's most prominent Muslim leader, Dalil Boubakeur, who is rector of the Grand Mosque of Paris, recently called for the number of mosques in the country to be doubled again – to 4,000 – to meet growing demand.

By contrast, the Roman Catholic Church in France has built only 20 new churches during the past decade, and has formally closed more than 60 churches, many of which are destined to become mosques, according to research conducted by La Croix, a Roman Catholic daily newspaper based in Paris.

Although 64% of the French population (or 41.6 million of France's 65 million inhabitants) identifies itself as Roman Catholic, only 4.5% (or 1.9 million) of those actually are practising Catholics, according to the French Institute of Public Opinion (or Ifop, as it is usually called).

By way of comparison, 75% (or 4.5 million) of the estimated 6 million mostly ethnic North African and sub-Saharan Muslims in France identify themselves as "believers" and 41% (or 2.5 million) say they are "practising" Muslims, according to an in-depth research report on Islam in France published by Ifop on August 1. The report also says that more than 70% of the Muslims in France say they will be observing the Islamic holy month of Ramadan in 2011.

Taken together, the research data provides empirical evidence that Islam is well on its way to overtaking Roman Catholicism as the dominant religion in France.

As their numbers grow, Muslims in France are becoming far more assertive than ever before. A case in point: Muslim groups in France are now asking the Roman Catholic Church for permission to use its empty churches as a way to solve the traffic problems caused by thousands of Muslims who pray in the streets.

In a March 11 communiqué addressed to the Church of France, the National Federation of the Great Mosque of Paris, the Council of Democratic Muslims of France and a Muslim activist group called Collectif Banlieues Respect called on the Catholic Church – in a spirit of inter-religious solidarity, of course – to make its empty churches available to Muslims for Friday prayers, so that Muslims do not have to "pray in the streets" and be "held hostage to politics."

Every Friday, thousands of Muslims in Paris and other French cities close off streets and sidewalks (and by extension, close down local businesses and trap non-Muslim residents in their homes and offices) to accommodate overflowing crowds for midday prayers. Some mosques have also begun broadcasting sermons and chants of "Allah Akbar" via loudspeakers in the streets.

The weekly spectacles, which have been documented by dozens of videos posted on Youtube.com (here, here, here, here, here, here, here, here and here), have provoked anger and disbelief. But despite many public complaints, local authorities have declined to intervene because they are afraid of sparking riots.

The issue of illegal street prayers was catapulted to the top of the national political agenda in France in December 2010, when Marine Le Pen, the charismatic new leader of the far-right National Front party, denounced them as an "occupation without tanks or soldiers."

During a gathering in the east central French city of Lyon on December 10, Le Pen compared Muslims praying in the streets to Nazi occupation. She said: "For those who want to talk a lot about World War II, if it is about occupation, then we could also talk about it [Muslim prayers in the streets], because that is occupation of territory. It is an occupation of sections of the territory, of districts in which religious laws apply. It is an occupation. There are of course no tanks, there are no soldiers but it is nevertheless an occupation and it weighs heavily on local residents."

Many French voters agree. In fact, the issue of Muslim street prayers – and the broader question of the role of Islam in French society – has become a major issue ahead of the 2012 presidential elections. According to a survey by Ifop for the France-Soir newspaper, nearly 40% of French voters agree with Len Pen's views that Muslim prayer in the streets resembles an occupation. Another opinion poll published by Le Parisien newspaper shows that voters view Le Pen, who has criss-crossed the country arguing that France has been invaded by Muslims and betrayed by its elite, as the candidate best suited to deal with the growing problem of runaway Muslim immigration.

French President Nicolas Sarkozy, whose popularity was at 25% in July – worse than any predecessor less than a year ahead of a re-election bid, according to the TNS-Sofres polling group – has been spooked by Le Pen's advance in the opinion polls. He now seems determined not to allow Le Pen to monopolize the issue of Islam in France.

Sarkozy recently called Muslim prayers in the street "unacceptable" and said that the street cannot be allowed to become "an extension of the mosque." He also warned that the overflow of Muslim faithful on to the streets at prayer time when mosques are packed to capacity risks undermining the French secular tradition separating state and religion.

Interior Minister Claude Guéant on August 8 told Muslims who have been praying on the streets of Paris that they should utilize a disused barracks instead. "Praying in the street is something that is not acceptable," Guéant said. "It has to stop."

Meanwhile, France ushered in Ramadan by inaugurating a new mega-mosque for 2,000 worshipers in Strasbourg, where the Muslim population has reached 15%. Construction also continues apace of a new mega-mosque in Marseille, France's second-largest city where the Muslim population has reached 25% (or 250,000). The Grand Mosque – which at more than 8,300 square meters (92,000 square feet) will accommodate up to 7,000 worshippers in a vast prayer hall – is designed to be the biggest and most potent symbol of Islam's place in modern France.

Boubakeur, of the Grande Mosque of Paris, says the construction of even more mosques – paid for by French taxpayers – would ease the "pressure, frustration and the sense of injustice" felt by many French Muslims. "Open a mosque and you close a prison," says Boubakeur.

But Turkish Prime Minister Recep Tayyip Erdogan has implied that the construction of mosques and minarets actually is part of a strategy for the Islamization of Europe. Publicly repeating the words of a 1912 poem written by the Turkish nationalist poet Ziya Gökalp, Erdogan said: "The mosques are our barracks, the domes our helmets, the minarets our bayonets and the faithful our soldiers."

Reflecting on the retreat of Catholicism and the rise of Islam in France, Archbishop Giuseppe Bernardini, an Italian Franciscan who heads the Izmir archdiocese in Turkey, and who has lived in the Islamic world for more than 40 years, has recounted a conversation he once had with a Muslim leader, who told him: "Thanks to your democratic laws, we will invade you. Thanks to our religious laws, we will dominate you."