French President Emmanuel Macron has announced he is extending a virtual lockdown to curb the coronavirus outbreak until 11 May, adding that progress had been made but the battle not yet won.

Acknowledging his country had not been sufficiently prepared early on to face the challenges posed by the outbreak of the new coronavirus, Mr Macron said the unprecedented restrictions put in place were showing results.

"The epidemic is starting to slow down. The results are there," Mr Macron said in a televised address to the nation. "Thanks to your efforts, every day we have made progress."

"But our country was not sufficiently ready for this crisis. We will all draw all the consequences," Mr Macron said.

Mr Macron's prime time address came as France ended a fourth week under lockdown, with residents ordered to stay at home except to buy food, go to work, seek medical care or get some exercise on their own.

After a relentless increase until the first week of April, the number of patients in French hospitals' intensive care units has started to decline, prompting health authorities to call a plateau in the deadly epidemic.

But if French hospitals are just about coping, helped by a massive effort to transfer patients by plane, helicopter or even high-speed train, nursing homes have been overwhelmed.

By today the coronavirus had claimed 14,967 lives in France, the fourth-highest death toll in the world, with more than 98,076 confirmed cases, according to official figures.

Mr Macron said that by 11 May, France would be able to test anyone presenting with Covid-19 symptoms.

Schools and creches would progressively re-open, he said.

Although Mr Macron's popularity initially shot up after he followed Italy and Spain in introducing drastic curbs on public life, his government has faced accusations of failing to address a shortage of masks and testing kits.