Italy on Thursday overtook China as the country worst affect by the highly contagious virus.
Italy's fatalities jumped by 793 to 4,825 in their largest one-day rise since the contagion emerged a month ago.
"What we all understand is that no member state can face this threat alone. The virus has no borders and the European Union is stronger when we show full solidarity," EU Commission head Ursula von der Leyen told Italy's Corriere della Sera newspaper.
Reported infections in Italy rose to 53,578 from 47,021, the Civil Protection Agency said. There were 2,857 people in intensive care, up from 2,655.
Late on Friday the EU Commission moved to formalise a deal reached by EU finance ministers on March 5 to suspend EU budget rules that limit borrowing, giving hardest-hit Italy and other governments a free hand to fight the disease.
Italy's failure to reduce its huge debt of 134% of gross domestic product would normally have drawn a rebuke from the EU executive, but von der Leyen said there were now other priorities.
"The Italian government will be able to put as much money into the economy as needed. Normal budget rules, debt rules for example, will not be applied at this stage," she said.
Brussels is expected next week to unveil a plan for using the euro zone's bailout fund, known as the European Stability Mechanism (ESM), which could unlock unlimited sovereign bond purchases by the European Central Bank.
"This work is ongoing," Commission Vice President Valdis Dombrovskis said in an interview with Reuters.
TOUGHER LOCKDOWN IN LOMBARDY
Lombardy, the northern Italian region around Milan which is the worst-affected by coronavirus, remains in a critical situation, with 3,095 deaths and 25,515 cases.
Lombardy's President Attilio Fontana asked businesses to close all operations excluding "essential" supply chains.
In a statement released late on Saturday, Fontana said weekly open markets must be halted as well as most offices and construction sites.
People will not be allowed to practice any outdoor sport, even individually, in the region.
The lockdown measures imposed in Italy earlier this month and emulated by several other countries in Europe, are likely to trigger a recession and heavy job losses.
Dombrovskis said the Commission is accelerating work on an EU-wide scheme to help the unemployed, scheduled for presentation in the fourth quarter.
The spreading coronavirus is infecting an increasing number of celebrities. Italian Serie A soccer champions Juventus said on Saturday the team's Argentinian striker Paulo Dybala has tested positive but has no symptoms, making him one of the most high-profile players to be infected so far.