EU summit struggles to agree climate pledge
EU leaders have so far failed to agree how much aid the bloc will give to developing nations to tackle the effects of global warming.
On the first day of a two-day summit in Brussels EU leaders had wanted to agree a joint offer of around 6bn euros ($9bn; £5.5bn) over three years.
But analysts say wealthier states are struggling to convince poorer Eastern European countries to contribute.
Officials said that consultations would continue overnight.
The BBC's Jonny Dymond in Brussels says there will be some serious arm twisting through the small hours as the EU tries to come up with the pledges.
"We will have a better figure tomorrow than we had tonight," Swedish Prime Minister Fredrik Reinfeldt told a news conference.
"We have [EU] member states with [International Monetary Fund] programmes, with huge deficits. This is on a voluntary basis, and already more than half of the states have provided figures."
The money being sought at the Brussels summit is for a "fast start" contribution to help the world's poorest nations tackle rising sea levels, deforestation, water shortages and other consequences of climate change between 2010 and 2012.
Several wealthy EU states have announced significant contributions, but it is not yet clear what Germany, France and Eastern European nations are ready to contribute.
As the summit got under way, pledges had been made for around 2bn euros.
The largest contributions came from Britain at 883m euros and Sweden - which currently holds the rotating EU presidency - at 765m euros. The Netherlands has pledged 300m euros and Denmark 160m.
The figures are totals spread over three years - 2010-2012.
President of the European Parliament Jerzy Buzek told EU leaders that "swift, binding, global decisions" were also needed on climate targets.
"I call upon you - put a figure on the table. We demanded this in the European Parliament resolution in November," he said.
As EU leaders arrived for the summit there was a moment of drama when Greenpeace activists breached the security cordon disguised as an official delegation.
They held up banners reading "EU: Save Copenhagen" before they were moved aside by security guards.
Financial matters will also be discussed at the twice-yearly summit.
Earlier on Thursday, momentum was building for a tax on bankers' bonuses. The leaders of France and Germany swung behind the idea after the UK announced a one-off supertax on bonuses in a pre-Budget report.
The enormous level of Greece's debt will also be a concern.
Greek Deputy Finance Minister Philippos Sachinidis said it stood at 300bn euros - its highest level in modern history.
EU Commission president Jose Manuel Barroso said on Thursday he was confident Greece would overcome its problems.
The European Council meeting is the first since the Lisbon Treaty came into effect and Belgium's Herman van Rompuy was elected as its first president.
---- from BBC news