Environment ministers from around the world were arriving in Copenhagen Saturday to ramp up pressure on climate negotiators working on a pact to curb global warming, as protesters gathered to demand that the world's leaders take strong action.

The ministers will have nearly a week of intense public and private talks before more than 100 heads of state and government come to the Danish capital at the end of next week.

On the chilly streets outside the conference center, police assigned extra squads to watch thousands of protesters gathering for a march to demand that leaders act now to fight climate change.

"All week we have heard a string of excuses from northern countries to make adequate reparations for the ecological crisis that they have caused," said Lidy Nacpil, of the Jubilee South Coalition. "We are taking to the streets to demand that the ecological debt is repaid to the people of the South," she said in a statement.

Pledges made to cut heat-trapping greenhouse emissions are far below what scientists say is needed to keep global temperatures from rising to potentially catastrophic levels.

A draft agreement was sent around Friday to the 192-nation conference, although it set no firm figures on financing or on cutting greenhouse gas emissions.

It said all countries together should reduce emissions by a range of 50 percent to 95 percent by 2050, and rich countries should cut emissions by 25 to 40 percent by 2020, in both cases using 1990 as the baseline year.

So far, industrial nations' pledges to cut emissions have amounted to far less than the minimum.

The draft also left open the form of the agreement — whether it will be a legal document or a political declaration.

Ian Fry, the representative of the tiny Pacific island of Tuvalu, made an emotional appeal for the strongest format, one that would legally bind all nations to commitments to control carbon emissions.

Speaking for citizens of atolls and islands around the globe that could be swamped by rising sea levels, Fry called on President Barack Obama to earn the Nobel Peace Prize he collected Friday by taking up the fight against climate change, which he called "the greatest threat to humanity" and international security.

"I woke up this morning crying, and that's not easy for a grown man to admit," Fry said, choking as he spoke in the plenary crowded with hundreds of delegates. "The fate of my country rests in your hands."

Todd Stern, the special U.S. climate envoy, called the text "constructive" but singled out the section on helping poor countries lower their growth of carbon emissions as "unbalanced." He said the requirements on industrial countries were tougher than on developing nations and the section was not "a basis for negotiation."

Environmental groups welcomed the text as a step forward, although they lamented the absence of what they considered essential elements.

The draft agreement, drawn up by Michael Zammit Cutajar of Malta, said global emissions of greenhouse gases should peak "as soon as possible," while avoiding a target year.

It called for new funding in the next three years by wealthy countries to help poor nations adapt to a changing climate, but mentioned no figures. And it made no specific proposals on long-term help for developing countries.

The funding is perhaps the hardest part.

As the draft was circulated Friday, European Union leaders announced in Brussels after two days of tough talks that they would commit $3.6 billion a year until 2012 to a short-term fund for poor countries. Most of this money came from Britain, France and Germany. Many cash-strapped former East bloc countries balked at donating but eventually all gave at least a token amount to preserve the 27-nation bloc's unity.

Still unknown is how much the wealthier nations, such as the U.S. and Japan, will contribute.