The Copenhagen climate summit's search for a deal to curb the world's greenhouse gas emissions won't succeed unless there is agreement on another thing too - money. Many of the countries which are most at risk from climate change are poor.
They say they can't afford to switch to cleaner energy generation or to defend their populations from problems such as drought and the rising sea level without help from rich countries.
Industrialised countries - which are historically responsible for emitting greenhouse gases - agreed to help such nations when they signed up to the UN climate change convention (UNFCCC), BBC News reports.
A planetary chain of protests headed by a mass rally in Copenhagen on Saturday cranked up the heat on problem-plagued talks over a pact to roll back climate change.
The centre of the Danish capital was in virtual lockdown, with thousands of police deployed or on standby ahead of a six-kilometre (four-mile) march that would take green and anti-capitalist demonstrators to the UN conference venue.
In Australia, organisers said around 50,000 people had taken to the streets nationwide, wearing sky-blue shoelaces in a call for a strong and binding agreement in Copenhagen.
In Hong Kong men, women and children marched, some dressed as pandas, while others held life rings bearing the slogan "Climate Change Kills. Act Now. Save Lives."
Indonesians rallied in front of the US embassy in Jakarta calling for help for developing nations in reducing greenhouse gases, AFP informs.
The United Nations proposed that rich countries pay to help poor ones curb pollution, while cutting their own emissions by at least 75% and possibly more than 95% by 2050 -- a suggestion that heightened tensions between the U.S. and China over climate change.
It isn't clear that the Copenhagen summit will yield a binding agreement on nations' efforts to combat climate changes. The U.N. document is the first official attempt to outline a substantive agreement from the summit.
On Friday, negotiations continued for a fifth day of the 12-day conference, with ministers from a number of countries directly participating in the talks. The draft proposal is vague in key areas to be discussed late next week, when many world leaders arrive, Wall Street Journal informs.