The French satirical magazine Charlie Hebdo is due to publish a cartoon of the Prophet Muhammad on the cover of its first issue since assailants killed 12 people at its offices.

The newspaper Liberation hosted Charlie Hebdo's staff as they prepared the new issue. Up to three million copies of its latest edition will be printed, which is 50 times more than usual.

The edition will appear on Wednesday in 16 languages, including Arabic, and will be sold in 25 countries.

Liberation published the Charlie Hebdo cover online late on Monday night, showing a man in a white turban holding a sign reading "Je suis Charlie."

Charlie Hebdo's past caricatures of the prophet appear to have prompted last week's attacks, which left a total of 17 people dead.

Al Jazeera's Rory Challands, reporting from Bobigny outside Paris, said that throughout the history of the magazine, Charlie Hebdo has tried to uphold the principle of freedom of expression.

"It has annoyed a lot of people, not just Muslims but also politicians and other religious communities," he said. "There will be people who’ll feel offended but this new issue but Charlie Hebdo says if they had done anything else, they would have succumbed."

Call for calm

The French Council of the Muslim Religion and the Union of French Islamic Organisations released a joint statement calling for Muslims to "stay calm and avoid emotive reactions" to the new issue.

Brothers Cherif and Said Kouachi and their friend, Amedy Coulibaly, were killed on Friday by police after the shootings at Charlie Hebdo offices and a kosher supermarket.

French police said on Monday that as many as six members of a terrorist cell involved in the attacks may still be at large.

Seeking to reassure a jittery nation in the wake of the attacks, French officials announced the unprecedented deployment of thousands of soldiers to boost security, including at Jewish schools.

"We have decided ... to mobilise 10,000 men to protect sensitive sites in the whole country from tomorrow [Tuesday] evening," Defence Minister Jean-Yves Le Drian said after an emergency security meeting.

"This is the first time that our troops have been mobilised to such an extent on our own soil," he added.

Another 5,000 security officers were also part of the reinforcements.

Meanwhile, the partner of one of the slain attackers behind the three-day killing spree in Paris crossed into Syria last week, according to the Turkish foreign minister.

Mevlut Cavusoglu said on Monday that Hayat Boumeddiene, 26, had crossed into Syria on January 8, the same day that her partner Coulibaly is suspected of killing a policewoman outside Paris on the second day of the attacks.