A source close to the government added that the date had been imposed on France by the plan of the United States, which is providing security at the airport, to pull out by August 31
Castex told TF1 television that the major steps taken to tackle fourth wave of infections in the country have been settled upon by a cabinet meeting of the government.
Faced with surging new coronavirus cases, Prime Minister Jean Castex announced the new measures last Thursday for around 20 million people living in Paris as well as regions in the north and south-east.
He said there were two options to contain the disease - a local week-end lockdown, already in place in other parts of the country, or a more broader lockdown in the region.
The health ministry also reported 296 new coronavirus deaths in hospitals, from 436 on Tuesday, bringing the cumulative death toll to 80,443. Total cases now stand at 3.38 million.
Castex also told a news conference that there was no need for a new national lockdown for now but and that if the pandemic gets out of hand, France will lock down again.
One in two intensive care beds are occupied by COVID-19 patients and non-essential procedures are still being postponed to ease the burden on hospitals.
Castex told parliament that the vaccine campaign in France would then be stepped up in January, with the elderly and other more vulnerable groups coming first in the queue.