Changing social distancing measures would, he said, "threaten a second peak in the spread of the virus", and as a result, they would stay. "The worst thing we could do now would be to ease up too soon," he added.

Germany's confirmed coronavirus cases had risen by 3,380 to 133,830, data from the Robert Koch Institute for infectious diseases showed on Friday.

German Chancellor Angela Merkel's conservative bloc has won support during the coronavirus crisis, hitting its highest level in nearly three years, a poll showed on Thursday.

Merkel's cautious approach appears to have reaped rewards, as a relatively early shutdown of schools, many factories and shops has had some effect and Europe's biggest economy has announced small steps toward a relaxation.

The DeutschlandTrend poll for ARD television put support for Merkel's Christian Democratic Union and its Bavarian sister party Christian Social Union at 38 percent, up 3 points from two weeks ago and its highest level since August 2017, just before the last federal election.