The ban - carried by a 75-30 vote in the Danish parliament - is due to enter into force on August 1.
"Whilst some specific restrictions on the wearing of full-face veils for the purposes of public safety may be legitimate, this blanket ban is neither necessary nor proportionate and violates the rights to freedom of expression and religion".
The ban also applies to false beards and masks.
The law does not ban "headscarves, turbans or the traditional Jewish skull cap", according to the report. The burqa covers the face completely, leaving a net screen for women to see through, while the niqab leaves the area around the eyes open.
The Danish parliament today passed a law banning the Islamic full-face veil in public spaces, becoming the most recent European country to do so.
Those who break the law could be fined 1,000 kroner (£118) for the first offence.
Those violating the law will have to pay a fine of 1,000 kroner (Rs 10,595).
Wearing of the burqa or niqab is, however, not common in the Nordic nation.
In February, when the Danish government formally proposed the face veil ban, Poulsen said that such veils were "disrespectful" to the community. Supporters of the ban say that covering the face is a form of oppression for women and poses security risks.
At least half of Germany's 16 states have bans on teachers and public servants wearing full-face veils.
Human rights group Amnesty International called the ban "a discriminatory violation of women's rights". "We would be happy to see governments addressing real problems and security issues that Muslim women face in their everyday life".
The justice minister underlined that police would be given instructions how to handle possible incidents and act "reasonably" and said it would apply "for all sorts of face-covering clothes".
But the European Court of Human Rights previous year upheld a Belgian ban on full-face veils, and said communal harmony trumped individual right to religious expression.