Dozens of Iranian students and clerics have gathered outside the French embassy in Tehran to protest against the publication of caricatures of Islam's Prophet Muhammad by a French satirical weekly.
Protesters chanted "Death to France" and "Down with the US" and burnt the flags of the US and Israel on Thursday, in a demonstration that lasted two hours.
The protest followed a week of protests and riots by Muslims in many countries who were angered by an anti-Islam video produced in the US.
In Paris, a little-known organisation called Syrian Freedom Association has filed a lawsuit saying the publication of the satirical cartoons publicly provokes discrimination, hatred or violence of an ethnic, racial or religious nature.
The case is currently being considered by courts in the French capital.
Al Jazeera's Jacky Rowland, reporting from Paris, said "authorities request that if anyone feels their rights have been violated, then the courts are the appropriate venue" through which to raise their concerns.
The government has already banned demonstrations planned for Saturday in Paris.
France announced that it would temporarily close its embassies and schools in 20 countries on Friday after Charlie Hebdo published cartoons of the prophet.
"We have indeed decided as a precautionary measure to close our premises, embassies, consulates, cultural centres and schools," a foreign ministry spokesman said of the shut-down set for Friday.
On Wednesday, France stepped up security and appealed for calm after the satirical weekly published the cartoons.
Laurent Fabius, the foreign minister, said he had ordered special security measures "in all the countries where this could pose a problem". Demonstrations across the Islamic world often follow Friday prayers.
Police were deployed outside the Paris offices of the magazine on Wednesday. The left-wing publication's offices were firebombed last year after it published an edition "guest-edited" by the Prophet Muhammad that it called Sharia Hebdo.
Prime Minister Jean-Marc Ayrault urged "responsibility" and said anyone offended by the caricatures could sue in court.
French schools and cultural centres in Egypt were closed on Thursday as a precautionary measure, the French consulate said.
"Although there has been no specific threat in Egypt, it has been decided as a precaution and as in other countries, to close French schools and cultural centres in Egypt on Thursday September 20," it said in a statement.
Appeal for calm
Leaders of the large Muslim community in France said an appeal for calm would be read out in mosques across the country on Friday but it also condemned the magazine for publishing "insulting" images.
French editor defends Muhammad cartoons publication
The cover of the magazine shows a Muslim in a wheelchair being pushed by an Ultra-Orthodox Jew under the title "Intouchables 2", referring to an award-winning French film about a poor black man who helps an aristocratic quadriplegic.
The weekly carries a total of four cartoons that include images definitively intended to represent the Prophet. In two of them, the Prophet is shown naked.
The explict - arguably vulgar - nature of the drawings made it inevitable they would cause offence.
The Charlie Hebdo editor told Al Jazeera that its website has crashed after it was hacked.
'Freedom of expression'
Ayrault said anyone offended by the cartoons could take the matter to the courts but made it clear there would be no government legal action against the weekly.
"We are in a country where freedom of expression is guaranteed, including the freedom to caricature," he said.
"If people really feel offended in their beliefs and think there has been an infringement of the law - and we are in a state where laws must be totally respected - they can go to court," Ayrault said.
He also said any request to hold a demonstration in Paris would be refused.
France's interior ministry has already banned all protests over the controversial video following a violent demonstration last weekend near the US embassy.
Charlie Hebdo's editor, Stephane Charbonnier, has defended the cartoons.
"I'm not asking strict Muslims to read Charlie Hebdo, just like I wouldn't go to a mosque to listen to speeches that go against everything I believe."
'Glory of the hero'
Muslims angered by cartoons mocking the Prophet Muhammad should follow his example of enduring insults without retaliating, Egypt's highest Islamic legal official said on Thursday.
Condemning the publication of the cartoons in France as an act verging on incitement, Egypt's Grand Mufti Ali Gomaa said it showed how polarised the West and the Muslim world had become.
His statement echoed one by Al Azhar, Egypt's prestigious seat of Sunni learning, which condemned the caricatures showing the Prophet naked but said any protest should be peaceful.
An official at the Coptic Orthodox Church in Egypt, whose population of 83 million people is 10 per cent Christian, also condemned the cartoons as insults to Islam.
Western embassies tightened security in the Yemeni capital Sanaa, fearing the cartoons could lead to more unrest.
Crowds attacked the US mission in Sanaa last week over the anti-Islam video.