File photo: French President Emmanuel Macron attends a meeting with health professionals as he visits a university health center, Tuesday, April 25, 2023 in Vendome, central France. AP
Last month he signed a law to raise the retirement age from 62 to 64, despite months of strikes against the bill.
He and his government have since tried to turn the page on the episode of popular discontent, one of the biggest challenges to his second mandate.
But protesters have booed and banged pots and pans at him on his forays into provincial France to meet members of the public.
When Macron attended a football match on Saturday, he was met with activists waving red cards.
Unions and the opposition are hoping for a mass turnout at the May Day rallies to let Macron know they continue to oppose the pension overhaul.
"I invite all French men and women... to go out and catch the sun, to tan while pushing their baby strollers in the streets of Paris and the rest of the country," Francois Ruffin, a member of parliament for the hard-left France Unbowed party, said on Sunday.
"We are making sure 2023 goes down in the country's social history," he told broadcaster BFMTV ahead of the public holiday.
Monday will mark the first time since 2009 that all eight of France's main unions have joined in calling for protests.
"This worker's 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.
"Red card" for Macron
Almost three in four French people were unhappy with Macron, a survey by the IFOP polling group found last month.
France has been rocked by a dozen days of nationwide strikes and protests against Macron and his pension changes since mid-January, some of which have turned violent.
But momentum has waned at recent strikes and demonstrations held during the working week, as workers appear unwilling to continue to sacrifice pay.
Protests in recent weeks have taken on a more humorous tone.
Demonstrators clanged kitchenware to drown out Macron during a speech to the nation after approving the pension law last month, and activists have kept up the practice on some of his visits around the country.
Near the Stade de France stadium outside Paris on Saturday, union activists distributed red cards and whistles to football fans coming to watch the final of the French Cup.
"A red card for retirement at 64," they read, ahead of the game in which Toulouse beat Nantes.
But security staff confiscated most whistles as supporters entered the stadium, and not a lot of protest was heard at the planned action time of 49 minutes and 30 seconds into the match.
That timing was a reference to the controversial article 49.3 of the constitution, which prime minister Elisabeth Borne invoked in March to ram the pension reform through parliament without a vote in the hung lower house.
Macron won a second five-year term last year, but lost his parliamentary majority in June elections.
Borne last week pledged to cut unemployment and make industry greener as she sought to move on to other affairs of state.
She also postponed any discussion on a controversial immigration bill until the autumn for lack of a parliamentary majority, saying she believed it was not the time for another divisive debate.
Labour unions early last month walked out of talks with Borne after she refused to budge on the pension reform's headline measure of raising the retirement age.
But CFDT union leader Laurent Berger on Sunday said that did not mean an end to all talks between unions and the government, even after the reform was signed into law.
If invited, "the CFDT... will go and talk like a union in a firm does with a boss -- even shortly after that boss did them a nasty turn", he said.