French Prime Minister Gabriel Attal says security measures will be stepped up with 4,000 extra soldiers deployed nationwide in the coming days. The country's terror threat was raised to its highest level on Sunday following a deadly attack in Moscow that was claimed by the Islamic State.

Four months ahead of the Paris 2024 Olympic Games, French authorities have raised the maximum alert level for terrorist threat.

President Emmanuel Macron said Monday that the Islamic State entity believed to be behind the Moscow attack – known as Khorasan, which is a branch in Afghanistan and Pakistan – had also sought to attack France.

At least 137 people were killed when gunmen stormed Moscow's Crocus City Hall on Friday evening before setting the building on fire.

The assault echoed an attack on the Bataclan music venue in Paris in November 2015 which left 90 people dead and was also claimed by the Islamic State group.

"This particular group made several attempts (at attacks) on our own soil," Macron told reporters during his trip to French Guiana.

French Prime Minister Gabriel Attal echoed this sentiment by saying that "the Islamist terrorist threat is real, it is strong" and "it has never weakened".

He said that 4,000 extra soldiers would be deployed nationwide in the days to come.

Attal said that 45 terror plots had been thwarted in France since 2017, two of them already this year.