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By Robert Mueller
PRAGUE, Feb 18 (Reuters) - The lower house of the Czech parliament approved the European Union's reform treaty on Wednesday, an important but not final step towards ratification in the central European country.
Government and opposition deputies approved the Lisbon treaty, by 125 votes to 61. It aims to make the EU's institutions more flexible after the bloc's expansion.
The treaty must be approved by all EU members to take effect and has yet to be approved in the Czech upper house, where it could still face weeks or even months of delays.
Many senators from the ruling right-wing Civic Democrat (ODS) party say the Czech Republic must first ratify a separate plan to host a U.S. missile defence shield radar base.
Most of the 27 EU member states have adopted the pact and the Czech delay has irked some EU partners who have pressured Prague, which holds the bloc's presidency until the end of June, to adopt the document quickly.
"I am glad the Lisbon treaty made it through the lower house," Prime Minister Mirek Topolanek said after the vote.
"The next battle will be in the Senate. We still have our congress declaration that ties (it) to ratification of treaties with the United States," Topolanek told reporters.
He said parliament also had to approve legislation that would clip the government's power -- granted by the Lisbon treaty -- to give up national authority in certain areas without prior approval by legislators.
The pact suffered a major blow when Irish voters rejected it in a referendum last year but Ireland plans to hold a new vote later in 2009. It also faces constitutional court challenge in Germany and has not been signed by the Polish president.
The pact would give the EU a long-term president, a stronger foreign policy chief, and would take away individual countries' veto rights in some areas.
SENATE STALEMATE
Some ODS members voted against the pact saying it would infringe national sovereignty and some have even threatened to quit the minority administration if the treaty passes.
The Senate, controlled by the Civic Democrats and their centrist allies, has delayed debate on the Lisbon treaty until at least April, demanding the lower house quickly pass the missile defence plans.
But the radar plan's chances of a swift passage appear remote as the government lacks a majority in the lower house and the opposition Social Democrats are against the scheme.
In addition, U.S. President Barack Obama has been cooler on plan than the previous administration. Some Civic Democrats have said that could drop their demand for the shield's ratification if Obama put the missile defence rollout in Europe on ice.
Even if the treaty passes through both chambers of parliament, eurosceptic President Vaclav Klaus could delay a pact he sees as a step towards a European superstate.
Klaus has hinted he would not sign the text until Ireland overturns its rejection of the treaty in a referendum last June. An Irish minister suggested on Monday a new vote could be held in October. (Writing by Jan Lopatka; Editing by Jon Boyle)