Germany is experiencing a "massive" pandemic of the unvaccinated, Health Minister Jens Spahn said Wednesday, calling for tougher action to tame a resurgence in Covid cases.

"We are currently experiencing mainly a pandemic of the unvaccinated and it is massive," Spahn told reporters. "In some regions in Germany intensive care beds are running out again."

Germany, Europe's most populous country with some 83 million people, has been grappling with a fourth wave of Covid-19 cases in recent weeks that has seen the seven-day incidence rate hit highs not seen since May.

The country added 20,398 cases over the past 24 hours, the Robert Koch health institute said Wednesday, while another 194 people died.

More than 66 percent of the population is fully vaccinated, but Spahn expressed frustration that the uptake of jabs has slowed and that a significant group of 18 to 59 year olds remain unvaccinated.

He also called for tougher checks at establishments or events where only those who can show they have been vaccinated, have recovered from Covid or have recently tested negative, are allowed to enter.

In some hard-hit regions, he said, access should be limited to those who are fully vaccinated or can show proof of recovery -- a system knowns as 2G in Germany.

"It's nothing to do with vaccine bullying," he said, "but with avoiding an overloading of the health care system".

His final recommendation was for a bigger push on booster jabs, saying the current pace "is insufficient".