Iceland is poised to become the first European country to outlaw male circumcision amid signs that the ritual common to both Judaism and Islam may be a new battleground over religious freedom.

A bill currently before the Icelandic parliament proposes a penalty of up to six years in prison for anyone carrying out a circumcision other than for medical reasons. Critics say the move, which has sparked alarm among religious leaders across Europe, would make life for Jews and Muslims in Iceland unsustainable.

One in three men globally is thought to be circumcised, the vast majority for religious or cultural reasons. Many Jews and Muslims fear the issue of circumcision could become a proxy for antisemitism and Islamophobia, pointing to similar tensions over religious dress and the ritual slaughter of animals for meat.

Muslim and Jewish leaders attacked the proposal, while Cardinal Reinhard Marx, president of the Catholic Church in the European Union, said the bill was a “dangerous attack” on religious freedom. “The criminalisation of circumcision is a very grave measure that raises deep concern.”

The Icelandic bill says the circumcision of young boys violates their rights and is incompatible with the United Nations convention on the rights of the child. It draws a parallel with female genital mutilation, already outlawed in most European countries.

The bill says circumcisions are performed without anaesthesia, and claims the procedure is often carried out “in homes that are not sterile, and not by doctors but by religious leaders. There is a high risk of infections under such conditions that may lead to death.”

It acknowledges that while parents have the right to give religious guidance to their children, “such a right can never exceed the rights of the child”. Boys who wish to be circumcised for religious or cultural reasons can do so when they reach an age at which they “understand what is involved in such an action”, it suggests.

Iceland’s population of about 336,000 includes tiny Jewish and Muslim communities. There are thought to be some 250 Jews and about 1,500 Muslims.

Silja Dögg Gunnarsdóttir of the centre-right Progressive party said she had proposed the bill after realising that there was no ban on male circumcision although FGM has been outlawed in Iceland since 2005. “If we have laws banning circumcision for girls, then we should do so for boys,” she said.

“We are talking about children’s rights, not about freedom of belief. Everyone has the right to believe in what they want, but the rights of children come above the right to belief.”

Nordic countries had well-deserved reputations for promoting human rights, she added. “If Iceland backs this, I think other countries will follow.”

The issue of circumcision has been raised in other European countries but none has outlawed it.

According to Milah UK, a Jewish campaign group to protect the right to circumcision, the procedure is only carried out by highly-trained and regulated practitioners, known as mohelim. Boys are usually circumcised at eight days old.

A spokesperson for Milah UK said: “Jewish male neonatal circumcision – known as brit milah – is a non-negotiable element of Jewish identity, common to Jews from all backgrounds and respected in liberal democratic countries. For a country such as Iceland, that considers itself a liberal democracy to ban it, thus making sustainable Jewish life in the country impossible, is extremely concerning.”

Parallels with FGM were unwarranted, Milah UK said. The partial or complete removal of female genitalia could make intercourse difficult and painful and cause serious medical complications. In contrast, circumcision was a minor procedure.

“There is no recognised long-term negative impact on the child for the rest of his life. Millions of men – Jews as well as others – are circumcised around the world, and are unaffected in their everyday lives by having undergone the procedure. Carrying out brit milah on newborn boys is a central requirement of Jewish law,” the spokesperson said.

Moshe Kantor, president of the European Jewish Congress, called for respect for the values of openness and tolerance, and added there was no evidence that circumcision was harmful.

“We can only assume that this attempt to ban a core practice of Jewish communities comes from ignorance about the practice and its effect on Jewish children, rather than to send a message that Jews are no longer welcome in Iceland,” he said.

Ahmad Seddeeq, the imam of the Islamic Cultural Center of Iceland, said the bill contravened religious freedom. “Circumcision has been practised for centuries, it is deeply rooted in cultural and religious traditions,” he said.

A meeting of religious organisations in Iceland was called earlier this month to discuss the bill, and they hoped to issue a declaration of opposition, he added.

Muslims in Iceland were already travelling to neighbouring countries to have the procedure performed on babies because of the reluctance of local doctors. But, Seddeeq said, “the [medical] benefits of this practice far exceed the risks”.

Jewish and Muslim communities warn that if circumcision is outlawed, the practice will go underground or religious minorities will travel or relocate to countries where it is permitted.

In Germany, a 2012 law permits only trained practitioners to perform circumcisions. It followed a controversial German court ruling which said circumcision “permanently and irreparably changed” a child’s body, and took away the individual’s right to “make his own decision on his religious affiliation”.

The following year, the Council of Europe passed a resolution calling on 47 member states to regulate practices concerning ritual circumcision, “to overcome some of the prevailing traditional methods, which do not take into consideration the best interest of the child and the latest state of medical art”. Israel said the resolution fostered “hate and racist trends in Europe”.

Two years ago, a judge sitting in a British family court said that young children should not be circumcised until they are old enough to decide for themselves. NHS advice is that “the risks associated with circumcisions when carried out by qualified and experienced doctors are small”.

The Icelandic bill comes against a backdrop of a number of European countries prohibiting Islamic religious dress, such as the niqab or burka. This spring the Danish parliament will debate a bill banning full-face veils in public.

Last year Belgium voted to ban halal and kosher meat, citing animal rights. Poland’s government has proposed a law prohibiting kosher slaughter, in a move vehemently opposed by the Jewish community.

The Icelandic bill on circumcision has cross-party backing and wide public support, Gunnarsdóttir said. If it passes its first reading, the bill will go into committee stage for several months before it can become law.