Activists launched a campaign on Monday to protect the right of Muslim women in Europe to wear Islamic headscarves.
The issue of the hijab -- the traditional headscarf worn round the head and shoulders -- has sparked controversy across the continent and underlined sharp divisions over integrating Muslims.
Some 250 delegates from 14 countries congregated at London's City Hall under the banner of a pro-hijab pressure group to campaign over what they see as human rights violations.
Among their most vociferous supporters was leading Muslim theologian Yusuf al-Qaradawi who called on France to overturn a ban on headscarves in schools, due to begin in September.
"The ban evokes a ghetto mentality," he told the conference. "You are antagonizing Muslims."
"Can this be comparable with civilization? This is certainly a step backwards. It is against religious and individual freedom," he said.
The Egyptian-born cleric, who has been banned from entering the United States since 1999, has been dogged by controversy on a week-long speaking tour of Britain.
British Jews formally complained to the police, accusing the theologian, who has condoned some suicide bombings, of inciting racial hatred. State prosecutors decided not to pursue the case.
The conference was picketed by gay rights activists who accuse the cleric of being homophobe and say he tramples on the rights of women.
At the conference, the French headscarf move was also condemned by London Mayor Ken Livingstone who said: "The French ban is the most reactionary proposal to be considered by any parliament in Europe since the Second World War.
"It marks a move toward religious intolerance which we in Europe swore never to repeat, having witnessed the devastating effects of the Holocaust."
But the issue has not just been confined to France. Several German states are to ban teachers from wearing headscarves.
Last month, the European Court of Human Rights rejected appeals by a Turkish student barred from attending Istanbul University medical school in 1998 because her headscarf violated the official dress code. Abeer Pharaon, coordinator of the pro-hijab movement, said there was a worrying trend developing across Europe from France and Germany to Belgium.
"The governments of some of these countries have claimed that they are protecting Muslim women from being 'forced' into wearing the hijab," she said.
"They think we are weak and controlled by our husbands and fathers. I assure you we are not. Muslim women are liberated, highly educated."
Her words were echoed by British Muslim convert Sarah Joseph who insisted the hijab was a symbol of choice. "The scarf is just a scarf," she said, "not a ball and chain."