President Emmanuel Macron summoned government ministers for a crisis meeting on Monday, as tensions ran high a day before another major day of strikes and protests against his pension reforms.

Nearly two weeks after Macron rammed the new law through parliament using a special provision sidestepping any vote, unions have vowed no let-up in mass protests to get the government to back down.

They have called for another big day of action on Tuesday, the 10th such mobilisation since protests started in mid-January against the controversial law, which includes raising the retirement age to 64 from 62.

Macron, whose approval ratings in opinion polls are at a low point, said last week he accepted the "unpopularity" that came with the reform.

His prime minister, Elisabeth Borne, meanwhile said that while there was no plan to drop the legislation, she was ready for fresh dialogue with unions.

"We have to find the right path... We need to calm down," she told AFP in an interview on Sunday.

Starting on Monday, Borne has scheduled talks over three weeks, including with members of parliament, political parties, local authorities and unions.

A state visit to France by Britain's King Charles III, which had been due to begin on Sunday, was postponed because of the current unrest.

- 'Very big move' -

Instead of hosting the UK monarch for a day of pomp and ceremony, Macron was instead due to meet Borne, other cabinet ministers and senior lawmakers for the crisis talks at the Elysee from 1:15 pm (1115 GMT), the presidency said.

Borne was to present the plan for consultations to the president at Monday's meeting, and then take it to Macron's allies and cabinet members, presidential sources said.

If unions accept her offer for talks, Borne is expected to put new measures on the table designed to ease the impact of the pensions law targeting physically demanding jobs, conditions for older workers and retraining.

But early reactions were not promising for the prime minister.

Laurent Berger, the head of the moderate CFDT union, who has taken an unexpectedly hard line against the pension reform, said he would accept the offer of talks but only if the reform was first "put to one side".

Berger called on the government to come up with a "very big move on pensions".

Left-wing firebrand Jean-Luc Melenchon said on Sunday that there was "a very simple way" to return to peaceful relations, and that was "to withdraw the law".

The protest movement against the pension reform has turned into the biggest domestic crisis of Macron's second mandate, with police and protesters clashing regularly in Paris and other cities since the reform was forced through.

- 'Highly disrupted' -

Last Thursday, the previous major protest day, police reported 457 arrests across France and injuries to 441 police officers.

Government spokesman Olivier Veran called Melenchon and his party "profiteers of anger", while Green party lawmaker Sandrine Rousseau accused Macron and Interior Minister Gerald Darmanin of stoking the unrest.

According to Paris mass transit operator RATP, metros and suburban trains will be "highly disrupted" on Tuesday.

Rubbish collectors in the capital are continuing their strike, with close to 8,000 tonnes of garbage piled up in the streets as of Sunday.

France's civil aviation authority has told airlines at Orly airport in Paris, as well as the Marseille, Bordeaux and Toulouse airports, to cancel 20 percent of flights for Tuesday and Wednesday.

French police have meanwhile come under severe criticism for heavy-handed tactics during recent demonstrations.

The Council of Europe said on Friday that peaceful protesters and journalists had to be protected from police violence and arbitrary arrest.

On Sunday the IGPN, the internal affairs unit of the French police, said it had launched 17 investigations into incidents since the protests began.