All sport in Italy, including England's men's and women's Six Nations matches and all Serie A games, will be played behind closed doors until 3 April in an effort to contain coronavirus, the government has said.
Italy is the worst-hit European country with some 3,090 cases and 107 deaths.
The Italian Cup semi-finals between Juventus and AC Milan and Napoli and Inter Milan were postponed this week.
The government decree was made on Wednesday evening.
England men's and women's sides play Italy in the Six Nations on 14 and 15 March.
The issue will be discussed at a meeting on Thursday by the Six Nations organisers and the individual countries - and the matches in Italy could be postponed rather than being played behind closed doors.
The decree, announced by Italian Prime Minister Giuseppe Conte, affects all areas of the country, including those places were the virus has not been found.
It also states that sporting clubs and organisations are responsible for checking their players and staff for coronavirus.
A government statement read: "There will be no sporting events with the presence of the public in order to prevent further contagion opportunities."The government's decree reads: "Sports events and competitions of all kinds and disciplines, held in every place, both public and private, are suspended; however it is permitted to carry out the aforementioned events and competitions behind closed doors, or outdoors without the presence of the public.
"In all such cases, the associations and sports clubs, by means of their medical staff, are required to carry out the appropriate checks to contain the risk of spreading the COVID-19 virus among athletes, technicians, managers and all accompanying persons who participate."
In Serie A many matches, including Juventus v Inter Milan last weekend, have been postponed rather than being played without fans.
However, after a meeting of club and Serie A representatives earlier on Wednesday, Inter chief executive Giuseppe Marotta said that playing without fans could be the only way of finishing the Serie A season.
"Playing behind closed doors could be the only way to complete the championship in the light of the emergency and the restrictions that the government is rightly adopting," he said as he left the meeting.
Juventus are also scheduled to play Lyon on 17 March in Turin in the second leg of their Champions League last-16 tie.
Last Thursday, Inter Milan's Europa League victory over Ludogorets was played behind closed doors at San Siro Stadium.
And last week Ireland's men's and women's Six Nations games against Italy in Dublin on 7 and 8 March were postponed because of coronavirus.
The Premier League has written to clubs to emphasise the importance of hygiene during to current coronavirus outbreak.
A number of clubs, including Wolves and West Ham, have advised players not to pose for selfies and sign autographs until the situation changes.