COPENHAGEN (Reuters) - Denmark's Prime Minister Mette Frederiksen said on Tuesday she was still recovering both physically and mentally from an assault in central Copenhagen last week and warned about more aggression in the public.

A 39-year old Polish man was remanded in custody over the assault which caused her to suffer a minor neck injury. The attacker was under the influence of alcohol and drugs at the time, and nothing indicated a political motive, authorities said.

"I'm not quite myself yet," Frederiksen said in an interview with broadcaster DR. "I look after my work as prime minister, and I always will. I was also able to do so over the weekend, but not in the same way as I normally do."

The assault happened just three weeks after Slovakia's Prime Minister Robert Fico was seriously injured in an assassination attempt.

Frederiksen said she has witnessed a shift in the public domain in recent years.

"We all experience across (political) parties that the boundaries are shifting wildly," she said.

"There's been threats over a long period of time, a very harsh tone on social media, which has gotten worse, and especially after the war in the Middle East, a lot of shouting in public, people behaving very, very aggressively," she said.

The small bicycle-friendly country ranks in surveys as one of the happiest in the world, and Danes pride themselves on their inclusiveness, equality and generous welfare model.

"We have been proud of a country where the prime minister cycles to work," she said.

"But a shift has occurred. I've always made myself available, but the street scene has changed, and there are places where we can no longer go, at least some of us politicians," she said.

(Reporting by Jacob Gronholt-Pedersen; Editing by Tomasz Janowski)