Elderly people may have to remain in isolation until the end of the year to protect them from the coronavirus, EU chief Ursula von der Leyen said on Sunday.
Countries across Europe are weeks into a lockdown in an effort to halt the spread of the virus.
"Without a vaccine, we have to limit as much as possible contact with the elderly," she told the Germany's daily paper Bild.
"I know it's difficult and that isolation is a burden, but it is a question of life or death; we have to remain disciplined and patient," she added.
"Children and young people will enjoy more freedom of movement earlier than elderly people and those with pre-existing medical conditions," she said.
Mrs von der Leyen said she hoped that a European laboratory would develop a vaccine towards the end of the year.
To ensure that people could be quickly vaccinated, authorities were in talks with producers on gearing up for world production, she said.