France will maintain its deployment of 10,000 troops that have been patrolling across the country in the wake of January's jihadist attacks at least "until the beginning of the summer."

"The threat of terrorist attack against our country remains high," the office of President Francois Hollande said in a statement after a special meeting of top ministers.

"The head of state has decided to maintain the level of the army on the national territory at 10,000 troops in support of security forces from the interior ministry."

It added that "7,000 of them are deployed primarily for surveillance and protection at religious sites that are particularly threatened."

Defence Minister Jean-Yves Le Drian later told reporters that the troops would remain deployed at least "until the beginning of the summer."

Soldiers have also been patrolling stations, media buildings and other potential targets since the jihadist attacks in Paris in January that left 17 dead.

Nearly half of sensitive sites protected by the army are in the Ile-de-France region where Paris is located, Le Drian said.