There was widespread rioting in Paris last Saturday, with national monuments including the Arc de Triomphe vandalised and more than 400 people arrested.
Now a spokesman for Mr Macron has told AFP: “We have reason to fear a great violence this Saturday.”
Despite a humiliating government U-turn on proposed green taxes on fuels, the Yellow Vests sense they can achieve more.
The group is named after the high visibility jackets that all motorists have to carry in France and originally called for a reduction in the price of diesel and petrol.
Car toppled during student protests against government reforms in central France
Riot police jump on and violently beat up a lone protester in Paris during Yellow Vest protests
Now disgruntled groups from Left and Right, including students and emergency workers, have joined their campaign.
This has ensured that Mr Macron’s approval rating – his lowest since he took office in 2017 - is now just 18 per cent, according to a new YouGov poll.
It was conducted the day before Saturday’s riots, with 1006 people making up a representative sample of the French population quizzed.
The 18 per cent figure represents a drop of three points and the third consecutive decline in three months.
Mr Macron came to power in May 2017 as an independent, pledging to reform the country’s sluggish economy and to introduce ecological measures in line with the Paris Climate Change agreement.
'Yellow vest' protestors in Paris smash and flip over a Porsche
But the former merchant banker is now described as “The President of the Rich”, and widely disliked among the French public.
Now he has issued an “appeal for calm”, as another day of action is planned for Saturday, not just in Paris but in other major cities and towns.
Mr Macron’s prime minister, Edouard Philippe, said: “What is at stake is the safety of the French people and our institutions. I call for responsibility.
“All the actors in the public debate – politicians, union leaders, journalists and citizens – will be accountable for their statements in the coming days.”
Social media is currently full of appeals for people to mass around the Champs Elysees in Paris on Saturday, so as to create disorder.
It will mean the fourth day of disturbances in a row, leading it to be dubbed “Act 4.”
The Sun Says
FRANCE’S riots are the direct result of President Macron’s ocean-going arrogance.
Hitting skint workers with higher fuel taxes and telling them it’s for their own long-term good is typical of him.
And after his aggression towards Britain . . . well, these woes couldn’t happen to a nicer bloke, could they?
But there is a warning there for us.
Exorbitant fuel prices are bad enough. Imagine telling 17.4million Leave voters their victory didn’t count.
The Sun warned yesterday that we fear civil disorder if a second referendum is called. Let’s be crystal clear: riots, or worse, are horrific, indefensible and the last thing anyone should want.
And we will not shrink from our view that second-vote campaigners are too glib about the forces they may unleash.
Moment 'Yellow Vest' protesters are battered by French police with batons after running into Paris Burger King to escape tear gas
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