Latest: Riot police in Paris have arrested 514 people as "yellow vest" anti-government protesters demonstrate in the city.
The protesters have tried to reach the French presidential palace in Paris, some scuffling with police firing tear gas, amid huge security aimed at preventing a repeat of last week's rioting.
Blue armoured vehicles beneath the Arc de Triomphe and rows of riot police blocked the demonstrators' passage down the Champs-Elysees avenue towards the heart of presidential power.
Officers frisked people and searched bags every hundred metres or so throughout central Paris, and even confiscated gas masks and protective goggles from Associated Press journalists.
Protesters who travelled to Paris from Normandy described seeing officers block yellow-vested passengers from boarding at stops along their route.
Police posted a video on Twitter of officers tackling a protester and confiscating his dangerous material, which appeared to be primarily a tennis racket.
— Sky News (@SkyNews) December 8, 2018
Paris police have fired tear gas on a group of yellow-vested protesters trying to march on the French presidential palace.
Groups in yellow vests also gathered near the Bastille plaza and a few other spots around Paris. The city subway system was shut down in the centre of town.
By noon, 514 had been detained in Paris, according to a police spokeswoman. No injuries have been reported.
Crowds of yellow-vested protesters have tried to march on the French presidential palace, surrounded by huge numbers of police bracing for outbreaks of violence after the worst rioting in Paris in decades.
Rows of riot police blocked the demonstrators’ passage down the Champs-Elysees avenue toward the heart of presidential power, firing tear gas and pushing them back with shields.
A ring of steel surrounded the Elysee Palace itself as police stationed trucks and reinforced steel barriers in streets throughout the neighbourhood.
A crowd of “yellow vest” protesters have marched down the Champs-Elysees avenue in central Paris surrounded by police security amid fears of new violence.
Hundreds of people gathered early on Saturday around the Arc de Triomphe, which was damaged in rioting a week ago. They then started walking peacefully down the avenue, lined with high-end shops normally bustling with Christmas shoppers but boarded up this Saturday amid worries of more looting and other damage.
A police spokesman said more than 170 people have already been detained on Saturday on suspicion of planning violence, although most were later released.
President Emmanuel Macron’s government is deploying 89,000 security forces around the country for protests against his reforms.
Prized Paris monuments and normally busy shopping meccas have been locked down after Mr Macron’s government warned that Saturday’s “yellow vest” protests in the capital will be hijacked by “radicalised and rebellious” crowds and become the most dangerous yet after three weeks of demonstrations.
The Eiffel Tower and Louvre Museum shut down along with hundreds of stores and businesses, fearing damage after rioting and looting last Saturday that saw 130 people injured and the worst urban unrest in Paris in decades.
Authorities are deploying barricade-busting armoured vehicles and 8,000 police in the capital alone.
The grassroots movement began as resistance against a rise in taxes for diesel and petrol, but quickly expanded to encompass frustration at stagnant incomes and the growing cost of living.
Mr Macron agreed to abandon the fuel tax hike, but that has not defused the anger, embodied by the fluorescent safety vests French motorists are required to keep in their cars.
Many members of the protest movement are calling for calm, and some struck a conciliatory tone after meeting the prime minister on Friday night, in a last-minute bid to cool tempers.
But the movement has no clear leaders, and past protests have attracted extremists who hurled projectiles at police.
“According to the information we have, some radicalised and rebellious people will try to get mobilised,” interior minister Christophe Castaner told a news conference.
“Some ultra-violent people want to take part.”
Mr Macron, the target of much of the protesters’ ire, has been largely invisible in recent days, leaving his prime minister and government to try to negotiate with protesters.
Out of the media spotlight on Friday night, he met riot police being deployed in Paris on Saturday.
Four people have been killed in accidents since the unrest began on November 17. Christmas markets, national football matches and countless other events have been cancelled or disrupted by the protests.
Parts of Paris looked like they were bracing for a hurricane, with boards on windows covering up the Christmas decorations.
Police removed any materials from the streets that could be used as weapons, especially at construction sites in high-risk areas.
“It’s with an immense sadness that we’ll see our city partially brought to a halt, but your safety is our priority,” said mayor Anne Hidalgo.
“Take care of Paris on Saturday because Paris belongs to all the French people.”
Demonstrations are also planned in neighbouring Belgium and in the Netherlands.
Neither country has proposed a hike in fuel tax, but hundreds of police officers are being mobilised in Brussels, where protesters last week clashed with police and torched two police vehicles. More than 70 people were detained.
Jan Dijkgraaf, editor of a Dutch “resistance newspaper” is also calling for peaceful protests in the Dutch cities of Amsterdam and Rotterdam.
- Press Association