French President Emmanuel Macron warned on Friday that the European Union is facing "a moment of truth" with the COVID-19 pandemic exposing the need for greater solidarity between member states.

Macron aligned himself with southern member states including Spain, Italy and Portugal, telling the Financial Times newspaper that there was "no choice" but for the bloc to set up a fund that "could issue common debt with a common guarantee".

These countries have backed so-called coronabonds which would pool member states' debt but the plan is opposed by the so-called Frugal Five member states which include Germany, the Netherlands and Austria.

The French leader warned that failing to strengthen solidarity between member states could spell the end of the bloc.

"If we can’t do this today, I tell you the populists will win — today, tomorrow, the day after, in Italy, in Spain, perhaps in France and elsewhere," he said.

"It’s obvious because people will say ‘What is this great journey that you [the EU] are offering? These people won’t protect you in a crisis, nor in its aftermath, they have no solidarity with you,’" he added

"They’re in favour of Europe when it means exporting to you the goods they produce. They’re for Europe when it means having your labour come over and produce the car parts we no longer make at home. But they’re not for Europe when it means sharing the burden'," he went on.

Macron's latest comments were released just a day after European Commission President Ursula von der Leyen issued a "heartfelt apology" to Italy over the bloc's slow response to the health crisis.

The EU chief told Parliament that "too many were not there on time when Italy needed a helping hand at the very beginning" but that the bloc had "now become the world’s beating heart of solidarity."

Italy is Europe's most-heavily impacted country with more than 22,000 deaths linked to COVID-19 reported in the country -- second only to the US.

Last month, Prime Minister Guiseppe Conte had already warned that the pandemic could make or break the European Union as Italy's health system struggled under the onslaught of cases and fatalities.

"If Europe does not show itself to be up to this task, the whole European project risks losing its raison d'être in the eyes of our own citizens," he stressed then.