BRUSSELS » A packed hearing on a petition calling for the protection of human embryos led to a rare outbreak of raucous exchanges in the European Parliament on Thursday — a sign that the battles over abortion and stem cell research that divide nations like Spain and the United States are making a serious incursion into European Union affairs.

The petition, which has garnered 1.8 million signatures, is a sign that the culture wars that have long colored national politics in some countries may be becoming increasingly salient across Europe. It also comes after recent demonstrations in France against same-sex marriage and government efforts in Spain to restrict abortion that signal support for socially conservative causes.

Leaders of One of Us, the group that brought the petition, told lawmakers that they were seeking to prohibit the use of European Union funds for research, foreign aid programs and public health activities that are linked to the destruction of human embryos.

"The problem here is with those who claim that an embryo, a fetus, is nothing," said Grigor Puppinck, president of the One of Us committee backing the initiative.

"It is understood that life begins at the point of conception and must be respected," said Puppinck, who also called for a ban on "the financing of abortion in development aid."

Puppinck was supported by numerous lawmakers affiliated with the center-right European People’s Party, many from Italy and Poland. But Puppinck and his supporters received criticism from other lawmakers, like Sophie in ‘t Veld, a lawmaker from the Netherlands.

"I would like to remind you that there are more than 500 million European citizens who have not signed your petition, and I will personally oppose your request until the bitter end," in ‘t Veld told Puppinck.

The petition was heard under a system introduced two years ago called the European Citizens’ Initiative. It is part of a renewed effort to bring citizens closer to the union, increasingly seen as an elite project led by faceless officials out of sync with the everyday concerns of Europeans.

To qualify, petitioners must receive at least 1 million signatures from a quarter of EU member states and then apply to the European Commission, the bloc’s executive arm, for formal recognition. Once accepted, petitioners are entitled to a hearing before the European Parliament.

The commission is not obliged to take any action by accepting such initiatives. But it must reach a formal decision within three months and justify that decision in writing. In the case involving One of Us, the commission must decide by May 28.

The hearing held Thursday generated so much interest that some people were turned away. Those who made it inside the hearing room gave standing ovations to their advocates and booed their adversaries, in one of the most raucous hearings some lawmakers had ever experienced.

In an interview, Puppinck attributed some of his support to the long financial crisis in Europe, which has eroded confidence in existing institutions and in future prosperity. Young people especially are seeking a society that is less governed by "selfishness and egoism" and want to lead "a more authentic life," he said.

Some of the loudest outbursts during the hearing came when Ana Gomes, a lawmaker from Spain, repeatedly asked whether the European Center for Law and Justice, an organization based in Strasbourg, France, of which Puppinck is director general, had any links with Pat Robertson, the American Christian evangelist.

Puppinck said in an interview that the European Center and the American Center for Law and Justice, a law firm and educational organization that Robertson had helped to establish, shared the same chief counsel. But Puppinck said he had never met Robertson, and he criticized Gomes for raising issues that were "not the point of the debate."

The petition has led civil society groups like the Center for Reproductive Rights and the German Foundation for World Population to ring the alarm, warning that funding for family planning and abortion-related services in low- and middle-income countries could meet stronger headwinds in coming years if the effort gains traction.

The initiative would "limit the EU’s ability to engage in international commitments" by jeopardizing aid totaling about $120 million spent each year on maternal and reproductive health, said Michael Cashman, a British lawmaker.

Other groups like the Wellcome Trust, a global health foundation based in London, have expressed concern about the prospects for research in areas like regenerative medicine and genetic disease.

That concern was echoed by Teresa Riera Madurell, a Spanish member of the European Parliament, who told the leaders of One of Us that adequate checks were in place to ensure that ethical standards are respected in stem cell research.

"The only thing your ban would achieve would be to slow down research at the European level, and that would have important implications for our competitiveness," she told the group.

The first petition to qualify as a European Citizens’ Initiative was brought by a group called Right2Water that collected 1.9 million signatures.

Last month, in response to that initiative, the commission pledged to improve access to clean water across Europe. But Right2Water immediately complained that the commission’s response lacked "any real ambition" and failed to offer a legal commitment ensuring that public, not private, companies provide water services.

Puppinck said he was prepared for a similar rebuff.

"My fear is that they say, ‘We have been listening to you very nicely, thank you for collecting 2 million signatures, goodbye,’" he said.

James Kanter, New York Times