"But this doesn't mean churches, respecting the law, are forbidden from speaking. Nor does it mean your words shouldn't go beyond the walls of your places of worship. That would be a strange idea of democracy: Everyone has a right to speak, except you," he told the leaders, including Paris Cardinal Andre Vingt-Trois.

Sarkozy said France's status as a "secular and social republic" was "written in black and white" in its constitution, along with its guiding principle of "laicite," or secularism.

However, he added that the country's religions should also participate in national debates and in "creating our cultural identities." He said it would be a "strange schizophrenia" to preserve France's religious heritage while insisting religions had "nothing more to say, offer and impart."

"The spiritual richness you animate, the depth of thought you embody, the values you bear all have a vocation to address themselves to those who never cross the threshold of your churches, mosques, synagogues and temples," the president told the religious leaders.

Catholics traditionally make up two-thirds of France's 60 million inhabitants, although fewer than one in 10 attends Sunday Mass, and 40 percent of the population denies any faith.

Church leaders rejected calls for changes in the application of "laicite" when a commission was set up in 2002 by the country's former prime minister, Jean-Pierre Raffarin.

However, Sarkozy, a Catholic, pledged to improve ties with religious communities before his May 2007 election. Since then he has called for religion to play a more prominent part in public life.

During a December 2007 visit to Rome, he said he believed "laicite," set out in a 1905 church-state separation law, should be interpreted "more positively" to enable religion to be seen "not as a danger, but as an advantage."

After another Vatican visit in October 2010, the president was accused by opposition politicians of violating the secularism principle by taking part in prayers at Rome's Basilica of St. John Lateran.

In his January speech, Sarkozy defended a controversial April ban on Muslim veils, which he said were "incompatible" the country's values and the "dignity of women."

However, he added that he was also deeply concerned by recent "aggressions against religious symbols," including attacks on Jewish and Muslim cemeteries, and said the country would guarantee all citizens "the right to practice their chosen faith."

"Not only does our republic guard against intervening in the religious sphere -- it will always be ready to defend those who are attacked or threatened because they believe, pray or witness publicly to their faith," the president said.

"Our republic will intervene immediately if citizens start affronting each other and will be implacable toward all those who seek even once to inflame the furnace of religious hatred on its territory. This ravaging hatred has sometimes been on the point of sweeping France away. Let things be clear: It will not do so again."

French newspapers said Sarkozy's speech was timed to rebut a Jan. 22 call by Francois Hollande, his main Socialist challenger in April-May presidential elections, for the 1905 separation law to be written into the national constitution.

Cardinal Vingt-Trois also criticized Hollande's proposal, as did Orthodox, Muslim and Jewish leaders.

In his speech, Sarkozy said he felt "truly comforted" by the presence of religious leaders, who demonstrated France had "created conditions for peaceful, harmonious and friendly coexistence between religions."

He added that Christianity had become a target in the country, and he praised Cardinal Vingt-Trois for "showing French Catholics are not living in an isolated camp and can respond to provocation with communion."

"As I've said many times, freedom of conscience is perhaps the most precious good guaranteed by our republican laws," the president told religious leaders.

"No religion will impose dogmas and precepts in France on those who wish to avoid them. But nothing can prohibit the idea of transcendence from being present in our society. The concord and harmony governing relations between the different religious currents here and irrigating the social body provide an excellent guarantee of peace," he said.