The lower house of the Czech parliament has passed the Lisbon Treaty.
The Chamber of Deputies granted its consent after a vote of 125 for and 61 against.
In the end, the pro-Treaty factions gained five more votes than the constitutional majority of 120 votes required.
A recent opinion poll suggested that more than six in 10 Czechs want the treaty ratified, amid concern that national prestige would suffer otherwise.
Full parliamentary ratification involves consent from the Senate, which is conditioning its approval of the treaty on a mechanism to control the transfer of national powers to Brussels.
That process could be delayed, as the Civic Democrats - who secured two postponements in the lower house - are the strongest party in the Senate.
It was Civic Democrat senators who challenged the treaty in the Constitutional Court in June last year, resulting in a delay of several months in the ratification process.
The court ruled in November that the treaty complies with the Czech constitution, despite fierce protests from President Klaus, who said it poses a threat to Czech sovereignty.
Mr Klaus has said he will delay ratification for as long as possible, following the example of Polish President Lech Kaczynski who is also reluctant to sign the treaty despite its endorsement by the Polish parliament.
