Pope Francis says the French priest killed by Islamic militants was on the road to sainthood

Announcement comes at a special Mass for pilgrims from the Rouen area of France where the attack took place

The late priest Jacques Hamel (AFP/Getty Images )

Pope Francis has said Father Jacques Hamel, the French priest knifed to death at his altar by Islamist militants in July, was a "martyr", indicating he was already on the road to sainthood.

Francis spoke at a special Mass for pilgrims from the Rouen area of France where Islamist attackers stormed into the church in Saint-Ã tienne-du-Rouvray, forced the 85-year-old Hamel to his knees and slit his throat while they chanted in Arabic.

"He accepted his martyrdom there on the altar of Christ," the pope said in his homily in the chapel of the guest house where he lives in the Vatican.

"He gave his life for us so as not to deny Jesus," Francis said, speaking in Italian. "He is a martyr and martyrs are beatified".

Beatification is one of the first steps in the complex process that leads to sainthood in the Roman Catholic Church.

Usually a miracle is needed for a candidate for sainthood to be beatified. But that requirement can be waived if there is evidence that the person died a martyr.

The Catholic Church posthumously confers sainthood on people considered so holy during their lives that they are now believed to be with God and can intercede with him to perform miracles.

In his sermon, Francis also called on all religions to declare that "killing in the name of God is Satanic".

Hamel's killing came as France's political leaders sought ways to defeat home-grown Islamist violence.

His murder by French citizens was the first Islamist attack on a church in western Europe and came just 12 days after a Tunisian who had pledged allegiance to Islamic State drove his truck through a crowd of Bastille Day revellers in the Riviera city of Nice, killing 84.

Reuters