The controls at France’s borders with other members of the visa-free Schengen zone, including Belgium and Germany, will “respect the principle of proportionality”, the French interior ministry said in a note to the EU which has just emerged.
The ministry said in the memo, dated October 3: “Risk analysis… confirms the existence of a persistent level of threat.”
It fears Islamist terrorists are planning further attacks on French soil.
Countries within the Schengen zone, including Germany and Austria, began re-introducing border controls in 2015, following a rise of refugees and migrants from the Middle East and Africa and a wave of deadly attacks by the terrorist group Islamic State (ISIS).
France re-introduced border controls on the night of November 13, 2015, after a group of ISIS militants launched a series of coordinated shootings and explosions across Paris, including the Bataclan Theatre, killing 130 people and injuring hundreds more.
It later came to light some of the attackers had entered the EU by posing as migrants, and others had been able to travel undetected across several EU borders in the lead up to the attack.
Salah Abdeslam, the sole survivor of the Paris ISIS commando, managed to cross the French border into Belgium on the night of the attacks.
Mr Abdeslam was briefly questioned by police, but quickly waved through the border; an administrative blunder (Mr Abdeslam was not known to French counter-terror police) that cast doubt on the future of the Schengen zone.
Germany also announced on Thursday it would be extending its border checks for another six months due to the “serious threat to public policy and internal security”.
Germany’s interior minister, Thomas de Maiziere, said during an EU interior ministers meeting on Friday Berlin remained committed to the free movement of people, but “at the moment could not do without border checks”.
Under EU rules, countries are allowed to impose the emergency controls for up to two years in September 2015, and in May the bloc urged them to respect the deadline.
But the need for border checks has become the new reality in Europe, and the bloc is working on changing its laws to allow for the introduction of such measures more easily and for longer periods.
France said its policy on border checks would stand until April 30 2018.