Sweden brokered the agreement on the first day of an important two-day EU summit being held in Brussels. The deal will give the Czechs an opt-out from a human rights charter attached to the treaty.

"The leaders have agreed the Czech opt-out. All the leaders applauded and cheered," a Swedish diplomat told Reuters.

A Czech government spokesman confirmed that an agreement had been reached on the treaty, which would streamline decision-making in the 27-member bloc.

The Lisbon Treaty must be ratified by the Czech Republic before it can come into force. Czech President Vaclav Klaus has so far refused to sign, saying that his country needs guarantees that it can opt out of a human rights charter. Klaus said the opt-out is necessary to shield the Czech Republic from property claims by ethnic Germans who were expelled after World War Two.

Britain and Poland also have opt-outs.

No agreement on climate funding

Swedish Prime Minister Fredrik Reinfeldt, who is chairing the meeting in Brussels, urged his counterparts to figure out a way to make good on its pledge to help developing countries fight climate change.

"Now is the time to formulate the EU climate mandate," Reinfeldt said.

According to the European Commission, poorer countries will need an annual sum of 100 billion euros ($147 billion) until 2020 to help fight global warming. The EU is prepared to contribute 15 billion euros to this annual figure.

Yet disagreements on where the money should come from persisted on Thursday. Britain has said it's willing to commit to funding. Other countries, such as Germany, have taken a wait-and-see approach. eastern European nations, headed by Poland, only want to help "based on their means."

Presidential hopefuls

If Czech President Klaus completes the ratification of the Lisbon Treaty, it will create a new, high-profile post of EU president. Although it wasn't part of the official agenda, European leaders couldn't avoid questions about potential candidates.

German Chancellor Angela Merkel, who was joined at the summit by the new foreign minister, Guido Westerwelle, wouldn't say who she'll support for the post.

"First of all, I'd like all countries to complete the ratification of the Lisbon Treaty," Merkel told journalists. "I am fairly optimistic that we will eventually manage this, and then I'll be prepared to talk about staffing."

Yet other leaders have already begun making their wishes known.

British Prime Minister Gordon Brown told reporters he believes his predecessor Tony Blair would make an "excellent candidate" for the position. Blair has not yet officially said he wants the job.

Several European leaders have said they will not back Blair, as Britain does not use the euro and is not part of the EU's Schengen border-free zone.

Spain's Prime Minister Jose Luis Rodriguez Zapatero said the top job should go to "a convinced European, with a European vocation to strengthen the union and all that is common about it."

Blair is not the only candidate for the top EU post. Luxembourg's prime minister, Jean-Claude Juncker, has signaled he would run if asked. John Bruton, Ireland's former prime minister, plans to seek the top EU post, his Fine Gael party said on Thursday. Latvia's former head of state, Vaira Vike-Freiberga, has also said she is interested in becoming the EU's first president.

th/AFP/dpa
Editor: Chuck Penfold