PRAGUE, October 24, 2009 (AFP) - The European Union's Lisbon treaty looked set to emerge from a limbo as the last hurdle to its ratification, Czech President Vaclav Klaus, nodded to a concession offered by the 27-nation bloc.

Klaus is the last EU leader holding out on signing the text, which aims to streamline EU decision-making and must be ratified by all members to take effect.

But on Friday the staunch eurosceptic accepted a proposal by the Swedish EU presidency to handle an opt-out from the treaty which he demands and which his critics take as another attempt to delay the ratification.

"This proposal corresponds to the president's expectations and he can continue to work with it," said Klaus's office.

Two weeks ago, Klaus asked for an exemption from the treaty that would prevent ethnic Germans forced out of his country after World War II from claiming back their property.

Britain and Poland won similar exemptions during the treaty negotiations in 2007 -- the deeply-Catholic Poland was assured it would not be forced to allow gay marriages, and Britain that EU laws and courts would not prevail over its own judicial system.

Seeing no chances that Klaus might yield, EU leader Sweden and the Czech cabinet set out to work on the wording of the exemption which they want to submit to the EU summit in Brussels on Thursday and Friday for approval.

Stefan Fule, Czech minister for EU affairs, suggested on Friday the Czech exemption would be a general one, comprising a comma and the words "Czech Republic" attached to "Great Britain" and "Poland" in the treaty's protocol.

The EU has been waiting in suspense for Klaus's signature, the last step in the Czech ratification process after local lawmakers approved the treaty earlier this year.

The impasse means that European Commission chief Jose Manuel Barroso, who was last month granted a second five-year term, is unable to nominate a new commission, because it is unclear what legal basis he should use.

The mandate of the current commission -- the EU's executive arm -- expires at the end of October.

Commission spokesman Johannes Laitenberger said a week ago the commission would stay on in a caretaker role until the future of the treaty is resolved.

But the body that draws up legislation impacting the lives of about half a billion Europeans and policing the application of EU laws is likely to remain a lame duck until the future becomes clearer.

This may take some time as Klaus also conditions his signature on a go-ahead from the top Czech court, which is assessing the treaty's compliance with the country's Constitution following a complaint filed by eurosceptic senators.

The senators are afraid the treaty will give too much power to Brussels -- in unison with Klaus, who refuses to fly the EU flag at his seat and who says the treaty threatens Czech sovereignty.

The court has said it will discuss the complaint in a public hearing on Tuesday, but declined to say how long the process might take.

Friday's statement by Klaus is a second glimmer of hope for the EU in a week after the president suggested on October 17 that he would ultimately sign.

"The train carrying the treaty is going so fast and it's so far that it can't be stopped or returned, no matter how much some of us would want that," he said, fuelling hopes that the treaty might take effect soon.