Emmanuel Macron faced police calls to bring in the army to defend Paris from "yellow vest" attacks following last weekend's riots.
The police unions' plea came as the Government held crisis talks with the leaders of all of France's political parties, many of whom urged the President to instantly scrap "green" fuel tax rises to avoid the country spiralling into a state of insurrection.
The three-week revolt has exposed a deep malaise over high taxation, the price of living and a sense of social injustice. Much of the ire has been directed against Macron, with many protesters complaining he is an arrogant and out-of-touch "president of the rich". Several regional state prefects - civil servants normally sworn to silence - were cited by Le Monde as criticising the "Parisian arrogance" of his Government, cut off from poor provincial France and in a "technocratic bubble" that was "without feelers".
Edouard Philippe, the Prime Minister, was due to announce new conciliatory "measures" in what observers are calling a "race against time" to prevent a fresh bout of violence. He has ordered a parliamentary debate on the crisis tomorrow.