France could see a new spike in Covid cases by the end of July due to the spread of the more contagious Delta variant of the virus, the government spokesman said Monday.

"Over the past week the epidemic is again gaining ground," Gabriel Attal told France Inter radio, with the Delta variant now accounting for 30 percent of new infections in the country.

A fourth wave of infections is "a possibility" by the end of this month, he said, echoing a warning issued by Health Minister Olivier Veran late Sunday.

Several countries, including Britain and Russia, have already seen alarming jumps in new cases because of the variant, which was first identified in India.

French officials acknowledge that not enough people are getting vaccinated despite ample supplies, which could lead to a rise in cases.

"We've seen in the United Kingdom an explosion (of cases) that occurred very rapidly after the first red flags, and we're seeing these signs in our country," Attal said.

Only 36 percent of France's population has been fully vaccinated with two doses
Only 36 percent of France's population has been fully vaccinated with two doses AFP / MARTIN BUREAU

Overall, the French infection incidence rate stood at 21 per 100,000 people as of last Thursday, the most recent data available, still below the alert level of 50 but an increase of 10 percent on the previous week.

"The English example shows that a wave is possible from the end of July," Veran had warned on Twitter, saying that a combination of vaccines, testing and social distancing can limit its impact.

Health authorities reported Sunday nearly 2,600 new cases over the previous 24 hours, also an increase from recent days, though far from the 35,000 daily cases seen at the height of the third wave that hit France in April.

Only 36 percent of the population has been fully vaccinated with two doses, though the government has ruled out making the shots mandatory.

Prime Minister Jean Castex will meet with local officials as well as party leaders in parliament this week to discuss requiring vaccines for health workers and retirement home staff.

The French hospitals federation (FHF) says vaccination rates have stagnated at 64 percent for hospital workers, with holdouts expressing doubts about the safety of the shots.