In separate, stark warnings, two major European leaders have bluntly told their citizens that the world needs to adapt to live with the coronavirus and cannot wait to be saved by the development of a vaccine.
The comments by Italian Prime Minister Giuseppe Conte and British Prime Minister Boris Johnson came as both nations around the world and US states are struggling with the increasing need to reactivate economies blindsided by the pandemic.
With 36 million people newly unemployed in the US alone, that economic pressure is building even as authorities acknowledge the risks of kicking off new waves of infections and deaths from a virus that people have no immunity to.
Britain and Italy have recorded the most coronavirus deaths in the world after the U.S.
Pushed hard by Italy's regional leaders and weeks in advance of an earlier timetable, Conte is allowing restaurants, bars and beach facilities to open Monday, the same day that church services can resume.
"We are facing a calculated risk, in the awareness ... that the epidemiological curve could go back up," Conte said late Saturday.
"We are confronting this risk, and we need to accept it, otherwise we would never be able to relaunch."
Conte added that Italy could "not afford" to wait until a vaccine was developed.
Health experts have said the world could be months, if not years, away from having a vaccine available to everyone despite the scientific gold rush now on to create a coronavirus vaccine or vaccines.
"We would find ourselves with our social and productive fabric heavily damaged," Conte said.
Italy's economy is forecast to contract 9% this year due to the impact of the coronavirus, which has prompted Europe's longest strictest lockdown.
For his part, British Prime Minister Boris Johnson, who was hospitalized last month with a serious bout of COVID-19, speculated Sunday that a vaccine may not be developed at all, despite the huge global effort to produce one.
"I said we would throw everything we could at finding a vaccine," Johnson wrote in the Mail on Sunday newspaper.
"There remains a very long way to go, and I must be frank that a vaccine might not come to fruition."
Johnson said Britain was taking 'baby steps' toward reopening, "trying to do something that has never had to be done before" moving the country out of a full lockdown."
"Despite these efforts, we have to acknowledge we may need to live with this virus for some time to come," Johnson wrote.
Coronavirus has infected 4.6 million people and killed over 312,000 worldwide, according to a tally by Johns Hopkins University of government reports, which experts say clearly undercounts the true toll of the pandemic.
The U.S. has seen over 88,000 people die and Europe has had at least 160,000 dead, including over 34,000 in Britain and nearly 32,000 in Italy.
Professional soccer matches in Germany's Bundesliga resumed over the weekend, a move keenly watched by the rest of the soccer world as well as American sports leagues like MLB, the NBA, the NFL and the NHL, which all face major changes to their operations amid the pandemic.
Germany has won wide praise for its widespread testing amid the pandemic, which some coaches said was the only way the league could resume. Not all fans were happy about the restart, which took place in empty stadiums, but the games were broadcast widely around the world.
Players were warned not to spit, shake hands or hug each other in celebrations after goals. Team staff and substitutes wore masks on the bench, and balls and seats were disinfected.
"The whole world is watching Germany to see how we do it," Bayern Munich coach Hansi Flick said. "It can act as an example for all leagues."
Churches throughout Greece opened their doors to the faithful after two months Sunday, while limiting the number of congregants and dispensing disinfectants. Turkey on Sunday allowed people over 65 to leave their homes for a second time 'up to six hours' but kept them under a general lockdown.
In Asia, China's commercial hub of Shanghai announced a June 2 restart of classes for younger students amid falling virus cases.