PARIS, Jan. 7 (Xinhua) -- The French government was considering a law to toughen sanctions against undeclared protests in order to stop a repeat of violence that marred "yellow vest" demonstrations in recent weeks, Prime Minister Edouard Philippe said on Monday.

"We must preserve the right to demonstrate in France and we must punish those who want to violate the law," Philippe told TF1 television following more wave of street protests that turned violent in Paris and main French cities at the weekend.

"That's why the government favors updating the law in order to sanction those who do not respect this obligation to declare protests, those who take part in undeclared protests, those who arrive at protests with balaclavas," he added.

Philippe also said the bill would be introduced after being discussed by the National Assembly where the ruling camp enjoys a large majority.

With protesters from the "yellow vest" movement calling on social media for ninth weekend of protest on Saturday, Philippe said 80,000 police nationwide would be deployed to stave off another round of violent social action that began on Nov. 17, 2018.

About 5,000 security forces would be mobilized in Paris where rioters torched cars, electric motors and barricades, punched and kicked riot police officers to the ground and used a forklift truck to invade a government building compound.

"We can not accept that some people take advantage of these demonstrations to break, to burn. Sometimes they come to break up, loot, sometimes to challenge the institutions," he added, stressing that "the thugs will not have the last word."

By the end of last year, people angry at higher fuel tax began blocking roads, occupying highway tollbooths and staging rolling nationwide protests.

Their movement have since turned into a bigger uprising denouncing a squeeze on household spending, high living costs caused by President Emmanuel Macron's fiscal policy which they say favors the rich.

Some of them asked Macron to step down and called for a "citizens' initiative referendum" to allow citizens to have stronger say to define the economic and social roadmap for the eurozone's second main powerhouse.

Two months on, the "yellow vest" movement which has no clear leader, is still posing a stern challenge to Macron, who is struggling to defuse public anger and meet protesters' requests, despite a series of concessions he made last month, including higher minimum wages and tax breaks.