Slovenia, which borders Italy, Austria, Hungary and Croatia, has confirmed 319 coronavirus cases and one person has died.
"The fact is that all terrain work had to be cancelled for an unforeseen length of time and that we have to question the new financial reality," race director Bogdan Fink said in a statement on the website of the race which had been scheduled to run from June 10-14.
The government prohibited all socialising in public spaces from Friday, threatening fines of up to 400 euros for people who did not respect the ban.
Schools, kindergartens, hotels, bars, restaurants and sports centres were closed earlier this week. Public transport and air traffic were shut down while many companies had to close due to lack of production parts.
Italy's Diego Ulissi and Vincenzo Nibali are among past winners of the Tour of Slovenia, as well as a local champion Primoz Roglic.
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