The EU legislature voted 525-119 with 29 abstentions to endorse the treaty which replaces a draft European constitution rejected by French and Dutch voters in 2005 referendums.
A handful of lawmakers dressed in yellow T-shirts brandished banners demanding a referendum on the treaty, which incorporates all the main reforms of the defunct charter.
European Commission Vice-President Margot Wallstrom told deputies the treaty signed in December "strengthens Europe's democratic legitimacy".
But British and Danish sceptics accused EU leaders of denying citizens a say on a text that is very close to the constitution in substance, though not in form.
The treaty provides for a long-term president of the European Council of EU leaders, a stronger foreign policy chief, a simpler, more democratic decision-making system and more say for the national and European parliaments.
It omits symbols of statehood such as a flag, anthem and motto, and adds "opt-out" clauses for Britain and Poland from the EU's Charter of Fundamental Rights and judicial cooperation.
"This is nothing less than a massive exercise in deceit," said Nigel Farage of the UK Independence Party, recalling that former British Prime Minister Tony Blair had promised Britons a referendum on the constitution.
Speaking for the EU presidency, Slovenian Secretary of State for European Affairs Janez Lenarcic responded: "There is nothing wrong with parliamentary ratification. All EU member states are representative parliamentary democracies."
European Parliament President Hans-Gert Poettering, a German Christian Democrat, said the assembly represented the people of Europe and told the protesting members: "If your parents could see you, they would be ashamed."
Only Ireland plans to hold a plebiscite. All 26 other member states intend to ratify the text by parliamentary procedure. Five countries have completed the process so far.
The European Parliament's approval is required as well as the unanimous ratification of member states for the treaty to enter into force.
Güncelleme Tarihi: 21 Şubat 2008, 11:57