As thousands of protesters gathered outside the UN climate change conference in Copenhagen on Saturday, activists in Vancouver did their own part to draw attention to global warming -- by marching in the nude.

Danish police estimate about 30,000 people took to street in the Danish capital this morning, demanding tough action by world leaders to curb climate change.

Meanwhile, a handful of Greenpeace activists were taking the fight to the streets of Vancouver, bracing the city's brisk winter weather unclothed in protest.

"I think taking off our clothes in the middle of the Vancouver winter shows the commitment that we have to this issue," spokesperson Andrea MacDonald said.

The event was just one of thousands of events held worldwide for the International Day of Climate Action.

Beginning at the Commercial Drive SkyTrain Station just before noon, participants stripped down and put on sandwich boards reading "Stop the Tar Sands" and "It's getting hot in here."

Protesters then rode the SkyTrain downtown, marching down Burrard Street then back up Granville before settling at the Vancouver Public Library at about 1:00 p.m.

MacDonald says the group was protesting out of lack of faith that Canadian representatives would take the talks in Copenhagen seriously.

"Canada is absolutely the worst country in these negotiations, they block the negotiations at every turn and it's completely because of the tar sands," she said.

B.C. NDP MLA Mable Elmore, who was at the library for a separate climate change rally, called the Greenpeace demonstration "creative," and agreed with their assessment of Canada's involvement in climate change talks.

"Our reputation on that level has deteriorated," Elmore said.

"I'd like to see the Canadian government step up and commit to playing a leadership role on the global stage."

The Copenhagen climate change accord

A draft accord, released Friday in Copenhagen, calls for wealthy nations to cut emissions by 20 to 40 per cent by 2020.

This would pave the way to reaching a broader goal of reducing worldwide greenhouse gas emissions by a whopping 50 to 95 per cent over the next 40 years.

To achieve both goals, 1990 emissions would be used as the baseline year.

Environment ministers from around the globe arrived in Copenhagen today for informal talks ahead of meetings with 110 world leaders, including Prime Minister Stephen Harper and U.S. President Barack Obama, late next week.

The summit aims to work out an agreement that will reduce greenhouse gas emissions that contribute to climate change and help poor nations deal with the effects of global warming -- from rising sea levels to reduced rainfall.

But it will likely be difficult for participants to agree on the massive financial commitments required for achieving that goal, which some analysts say could amount to US$150 billion per year.

No financial terms were included in the draft. However, it calls for all countries together to reduce emissions by 50 to 95 per cent by 2050.

"It's time to begin to focus on the big picture," Yvo de Boer, the top UN climate official, said Friday. "The serious discussion on finance and targets has begun."

The draft calls for action similar to the 1997 Kyoto Protocol, which legally binds signatories to emission-reduction targets and imposes penalties for failing to meet them.

With files from The Associated Press