"The prime minister will need to present his resignation in the coming hours, as is customary ... during the day, I think," government spokesman Christophe Castaner said on Monday. "And in the next few days a new government will be formed, I think under the authority of Edouard Philippe."
With 350 seats LREM and its Modem allies have an overwhelming majority, even if it is not as large as some opinion polls predicted.
Castaner dismissed the shortfall as a "rich people's problem" for a party that did not even exist two years ago.
France's 2017 parliamentary election - final results
The definitive results issued by the Interior Minister on Monday morning were:
- Republic on the Move and Modem: 350 (43.06% + 6.06%)
- Republicans, UDI, various right: 137 (22.23%, 3.04%, 1.68%)
- Socialists, Left Radicals: 32 (5.86%, 0.36%)
- France Unbowed, Communist Party: 27 (4.86%, 1.20%)
- Various left: 11 (145%)
- National Front, far right, France Arise: 10 (8.75%; 0.11%, 0.10%)
- Regionalists: 5 (0.76%)
- Greens: 1 (0.13%)
The result was marred by a record low turnout, with 57.36 percent of the electorate not voting, 2.95 percent casting blank votes and 1.25 percent spoiling their ballot papers.
"We have won a net majority but at the same time the French people did not want to give us a blank cheque," Castaner admitted.
So far as LREM voters were concerned, that was perhaps due to a feeling that the battle was already won, he added.
"The people have started a civic general strike," was the comment of hard-left leader Jean-luc Mélenchon, who won a seat in Marseille and heads another newly formed party, which won 17 seats.
Had any ministers failed to be elected they would not have been invited to join the new cabinet. But the six who did face a second-round contest succeeded in winning.
The reshuffle will not be a major one, according to Castaner.