Monday will see Macron's second address to the Congress, a joint meeting of France's National Assembly and Senate.
Last year he declared his intention of reforming the constitution, this year the project has been launched with discussions in parliamentary committee last week to be continued next week and after the summer holiday.
The main proposals are:
- a 30-percent reduction of the number of MPs;
- speedier parliamentary procedures;
- a ban on serving more than three successive mandates;
- the introduction of 15 percent proportional representation in parliamentary elections.
That is a "bazooka attack" on the National Assembly, according to 78 of the 98 MPs from the mainstream-right Republicans, who signed a declaration in the Journal du Dimanche paper on Sunday.
They complain that the reforms do not address what they believe to be French people's chief concerns - immigration, law and order and the economy.
A parliament that is "as unstable as it is weak", will lead to Italian-style political instability, they claim, adding that the changes, if adopted, would represent "the triumph of technocracy over democracy".
France Unbowed boycott
While most of the Republicans will attend the congress, some have decided to boycott it in protest.
They are following the example of the hard-left France Unbowed party, whose 17 representatives will stay away because "the monarchy's time has passed", as one of their number, Eric Coquerel, put it.
The congress will be a PR exercise for Macron, according to the party.
But their sometime allies, the Communists, who boycotted last year, will go this year to try to "limit the powers of the hyperpresident", while the more centrist Socialists will also attend.
The changes must be approved by both houses and the congress or be put to a referendum and the final parliamentary vote should take place at the beginning of next year.