Police in Demark say more than 25,000 marched in protest of the U.N. climate conference in Copenhagen, demanding more aid from the United States and a stronger commitment from President Obama to combat global warming.

“Pay the climate debt, America,” Dustin, a protester from Taiwan, said. “We think the world needs an ambitious climate treaty. My country is suffering from climate change. Several villages were buried this year.”

Rik Lindhardt from Sweden added: “I think the U.S. and China are fighting over small things and no one wants to take responsibility. They can both do more.”

On Friday, Obama is expected to pledge several billion dollars to help vulnerable, developing countries deal with the effects of climate change. European Union nations have agreed to give about $3.6 billion.

“I don’t like it, it’s not enough,” said Anne Heupel of Copenhagen. “They don’t want to sacrifice for the developing countries. The whole world needs to stand together.”

Poor and vulnerable nations, like Bangladesh and several Pacific Island nations, want a $200 billion commitment so they can temper the potential impacts of global warming – ocean flooding, drought, disappearing forests and increased diseases.

The World Bank says the developed nations should offer upwards of $50 billion a year to "kick start" a global climate mitigation and adaptation fund through a binding, legally enforceable commitment, something India and China refuse to accept.

Many of the protestors blamed the U.S., Europe and Australia for an energy-rich, luxurious lifestyle that requires vast amounts of fossil fuel per capita.

“A lot of rich countries have been making huge profits since the Industrial Revolution. It is time to pay the price,” said Martin Cubby from Sydney, Australia. “It is up to the rich countries to make sure we have a safe planet in the future.”

President Obama is expected to speak to the UN delegates here on Friday, along with dozens of other world leaders.

Obama has pledged a 17 percent reduction of greenhouse gases below the 2005 benchmark by 2020. That is just 4 percent below 1990 levels. Most scientists say the world needs to cut those emissions from the 1990 levels by 25 percent to 40 percent to avert a climate crisis.

“They can do better. To save the climate the American president should be more aggressive,” said Tanya Griesner from Hamburg, Germany. “We all have to do better."

Germany and most European nations say they are willing to cut their emissions from 1990 levels by 30 percent if the U.S. would agree. A cut of 15 percent would cost the typical American family at least $1,300 a year, according to CBO figures from last year.

Not everyone agreed with the protesters. A young economist from Copenhagen watched as the crowd march by.

“In a hundred years people will say, why did we do so much for the climate, when you could have done so much for the people starving," he said.