Speaking early Tuesday after a lengthy video call with the country's 16 state governors, Chancellor Angela Merkel announced that restrictions previously set to run through March 28 will now remain in place until April 18.

Coronavirus infections have increased steadily in Germany as the more contagious variant first detected in Britain has become dominant, and the country's daily number of cases per capita has passed that of the United States.

"We basically have a new pandemic," Merkel told reporters in Berlin.

"Essentially we have a new virus, obviously of the same type but with completely different characteristics," she added. "Significantly more deadly, significantly more infectious (and) infectious for longer."

Since their last meeting three weeks ago, which saw the two sides agree a multi-step plan to relax restrictions, several states have tried to avoid going back into tougher lockdowns when the weekly number of new infections exceeds 100 per 100,000 residents on three consecutive days.

Merkel made clear that she wouldn't accept that.

"Unfortunately, we will have to make use of this emergency brake," she said.

The weekly infection rate per 100,000 people stood at 107 nationwide on Monday, up from the mid-60s three weeks ago.

Officials agreed to largely shut down public life from April 1-3, adding a public holiday and shutting down most stores for the period. Public gatherings will be banned from April 1-5, to encourage people to stay at home.