The government faced calls Tuesday to bolster free speech amid concern that French satirical magazine Charlie Hebdo could not be published in Australia under existing race discrimination laws.

Canberra last year abandoned plans to repeal a section of the Racial Discrimination Act that makes it illegal to "offend, insult or humiliate another" because of their race after concerns from ethnic communities.

A suspect accused of killing four people in a supermarket siege outside Paris last week had been on a U.S. terror watchlist, CNN reported Monday. 

Amedy Coulibaly, who is suspected of taking hostages and slaying four Jewish shoppers at the Hyper Cacher kosher supermarket to the east of the city, had been on a U.S. terror database "for a while," a law enforcement official told CNN. 

Hackers claiming to be Islamists have hijacked hundreds of French websites since the attacks on the satirical weekly Charlie Hebdo, flooding them with jihadist propaganda.

Homepages of several French websites have been replaced by phrases like "There is no God but Allah", "Death to France" or Death to Charlie" written against a black background, often with the signature #OpFrance. The technique termed "defacement" consists of taking control of an internet site and modifying its content.

Al-Qaida in the Islamic Maghreb warned France on Monday to expect new attacks over its hostility to Islam, and praised jihadists behind last week's Paris killings.

"France is paying today the price of its aggression against Muslims and its hostile policy towards Islam," AQIM said in a statement posted on jihadist websites.

The White House admitted Monday it should have sent a senior official to the massive rally against terrorism in Paris, as President Barack Obama came under fire for failing to travel to France.

"We should have sent someone with a higher profile to be there," White House press secretary Josh Earnest said.

Bulgaria has arrested a Frenchman wanted in his own country for terrorism and who allegedly planned to take his son to receive a radical Islamist upbringing in Syria, prosecutors said Monday.

Fritz Jolie Joaquin, 29, a French citizen of Haitian origin, was arrested while trying to cross Bulgaria's southeastern Kapitan Andreevo border checkpoint with Turkey on a bus on January 1.

Less than a week after bloody terror attacks left 17 people dead, France's top legal body will review a decree stripping a convicted terror operative of his naturalized French citizenship.

France's Constitutional Council on Tuesday begins examining the case of Ahmed Sahnouni, a Moroccan naturalised by France in 2003, and who was convicted to a seven-year prison term in March 2013 for activities in a terror organization.

European nations have pushed for tighter anti-terror controls after last week's Islamist attacks in Paris, but concerns about civil liberties and intelligence sharing may limit their arsenal, analysts said Monday.

Security ministers from several EU nations, the U.S. and Canada pushed for urgent steps to counter the growing jihadist threat as they met in Paris on Sunday amid the shock wave from the carnage in the French capital.

This week's edition of Charlie Hebdo, put together by survivors of last week's newsroom massacre in Paris by Islamist gunmen, will defiantly feature caricatures of the Prophet Mohammed, its lawyer said Monday.

The special issue, to come out on Wednesday, will also be offered "in 16 languages" for readers around the world, one of its columnists, Patrick Pelloux, said.

Progressive Socialist Party chief MP Walid Jumblat said on Monday that targeting Jabal Mohsen and the Alawites “serves the purpose of the Syrian regime,” as he strongly condemned the double suicidal bombing that rocked the pro-Assad Tripoli district.

He also stressed his support for Sunday's rally against terrorism in France while questioning the participation of Israeli Prime Minister Benjamin Netanyahu.