Janice Grey, a Canadian youth delegate from northern Quebec's Nunavik region, takes part in a peaceful sit-in youth protest Wednesday in Copenhagen. The group was later removed by police. ((Patricia Bell/CBC))

The United Nations says it will re-evaluate how representatives from non-governmental organizations are given access to its climate change conferences because of violence and other incidents in Copenhagen.

Representatives from 1,500 non-governmental groups were accredited to attend the UN climate talks in the Danish capital, but after several days of protests and demonstrations, the UN decided on Wednesday to limit the number of participants.

Daniel Vockins, a conference participant from London, England, was upset that some non-governmental groups were being denied access to the summit.  

"I would say it's a travesty, really, to be deciding the future of the entire world without the people who will be affected by those changes," Vockins said.

Yvo de Boer, executive secretary of the UN climate change secretariat, said concern for safety of staff and world leaders led to the restrictions.

De Boer said protesters organized flash mobs, disrupted meetings and climbed onto the podium during speeches.

Danish police detained more than 200 protesters Wednesday who tried to get through the security perimeter around the Bella Centre, the suburban site where the conference is being held.

Michael Miltenberger, the environment and natural resources minister for the Northwest Territories, said it’s clear a review is necessary before future UN climate talks.

"Next time, yes, there's going to be a serious review of how do we do this," Miltenberger said. "They're all going to be looking at the issue of NGO and civil society representation because it has been so problematic."

Miltenberger said organizers of the Copenhagen summit expected 15,000 to 20,000 people from non-governmental organizations, but more than 45,000 people showed up.

Canadian Prime Minister Stephen Harper and other world leaders may extend their stay in Copenhagen to Saturday as part of a last-ditch, overtime effort to reach a deal at UN climate talks.

with files from The Canadian Press