The leaders of Britain and Italy have warned that the world cannot wait for a coronavirus vaccine.
Italian Prime Minister Giuseppe Conte and UK Prime Minister Boris Johnson said citizens would have to adapt to living with the virus.
Mr Conte is allowing restaurants, bars and beaches to open from Monday, and for church services to resume and shops reopen.
"We are facing a calculated risk in the awareness that the epidemiological curve could go back up," he said.
"We are confronting this risk and we need to accept it, otherwise we would never be able to relaunch."
Mr Conte said Italy could "not afford" to wait until a vaccine was developed.
Mr Johnson wrote in the Mail on Sunday newspaper: "I said we would throw everything we could at finding a vaccine.
"There remains a very long way to go and I must be frank that a vaccine might not come to fruition."
Mr Johnson was last month admitted to intensive care with Covid-19.
Professional soccer matches in Germany's Bundesliga resumed over the weekend and were keenly watched by the rest of the football world.
The games took place in empty stadiums, and players were warned not to spit, shake hands or hug each other to celebrate goals.
