On Labor Day, hundreds of thousands of people gathered in France to protest President Emmanuel Macron's pension reform, with unions pledging to continue their struggle even after the changes were signed into law.

Unions have been hoping for a vast turnout across France for the May 1 protests to further rattle Macron, who has been greeted by taunts and jeers as he toured the country seeking to defend the reforms and relaunch his second term.

Macron last month inked a law to raise the retirement age from 62 to 64, in spite of months of strikes against the bill.

"The law has been passed but has not been accepted, there is a desire to show discontent peacefully to have a reaction in response that shows a certain level of decency," said Celine Bertoni, 37, an academic in the central city of Clermont-Ferrand as quoted by AFP.

"I still hope that we are going to be told it will be withdrawn," she added.

On her account, Karine Catteau, 45, in the western city of Rennes, said as quoted by AFP that "Macron has the impression that as he was elected he has all the power! But I want him to cede his place to the people." 

At 1200 GMT, the main protest march in Paris began along the customary protest route from Place de la Republique to Place de la Nation, with a sudden heavy downpour starting as it did.

VIDEO: The European Union 2023 🇪🇺 : Wounded on the ground after police attack Labour Day marchers in #Paris 🇫🇷 . pic.twitter.com/vhvwUs1jqF #vonderLeyen #Macron #manifs1ermai #LabourDay #France #TomorrowsPapersToday #ViolencesPolicières #Labour

— Manchester Chronicle 🐝 (@WithyGrove) May 1, 2023

Videos posted on social media largely showcased French police brutality as they used stun grenades and rubber bullets -- which are prohibited in most European countries -- against protesters.

'Resentment and anger are not diminishing'

One of the major obstacles to Macron's second term has been the episode of public discontent, which his administration has worked to overcome.

"The page is not going to be turned as long as there is no withdrawal of this pension reform. The determination to win is intact," said the head of the CGT union Sophie Binet at the Paris protest.

"The mobilization is still very, very strong," added Laurent Berger, head of the CFDT union.

"It is a sign that resentment and anger are not diminishing."

The eight major unions in France came together for the first time since 2009 to call for protests on Monday.

"This workers' holiday will take place amid union unity and that alone is historic," said Frederic Souillot, the secretary general of the Force Ouvriere (Worker's Force) union.

Since mid-January, France has experienced 12 days of nationwide strikes and protests against Macron and his pension reforms, some of which have descended into violence.

On Saturday, when Macron went to the French football cup final, he was greeted by protesters holding red cards. According to a study released last month by the IFOP polling organization, over three-quarters of French citizens disapproved of Macron.