Lawmakers approved the move in a bill passed late Tuesday, in a rare success for the government, whose tough-talking interior and justice ministers Bruno Retailleau and Gerald Darmanin have been pushing for the legislation.

The French government has vowed to intensify the fight against narcotics and drug-related crime, with Retailleau saying in February that France was confronting a "white tsunami" of narcotics.

The right-leaning Senate backed the bill on Monday and a majority of lawmakers in the lower-house National Assembly gave it a green light on Tuesday evening.

The law means some of France's most dangerous drug traffickers will be locked up in two top-security prisons, the first from July, under a system inspired by similar measures in Italy to tackle the mafia.

The new legislation will also see the creation of a specialised prosecutor's office and national investigation unit to deal with the most complex drug-related crimes.

The law also allows prosecutors to keep certain investigation techniques secret from alleged traffickers and their lawyers in very specific cases, in a move that has been criticised on the left as infringing on their right to defence.

Darmanin on Tuesday evening hailed parliament's vote as a "big step", while Retailleau welcomed what he called a "decisive stage" allowing authorities to fight "on equal terms against those who poison the lives of our fellow citizens".

The hard-left France Unbowed party voted against the bill, as did several others on the left, over the proposed law being too repressive.

The National Assembly vote came after unknown assailants earlier this month carried out a wave of attacks on vehicles and buildings seemingly intended to intimidate prison guards.

Twenty-eight people in total have been detained over the coordinated attacks, according to the National Anti-Terrorist Prosecutor's Office leading the probe.

The attacks are "clearly linked to drug trafficking," Darmanin said on Wednesday morning.

Five among those in custody had "fired a Kalashnikov at the homes of prison guards," he told the France Inter radio broadcaster.

They did it "because they do not want to go into the prison system that I am currently creating, which aims to isolate them from the rest of the world," Darmanin said.

The justice minister has pushed for tougher security after assailants last year attacked a prison van carrying drug baron Mohamed Amra at a highway tollbooth, freeing him and killing two prison guards.

Amra has since been re-arrested in Romania and extradited back to France, where he is being held at one of the two future high-security prisons.

The International Prisons Observatory watchdog has criticised Darmanin's plan, saying it was based on a "security obsession" and included measures violating "human rights".

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