Relief in Parliament contrasts with ugly street battles as right-wing protest turns violent after French gay marriage law clears last hurdle

Running battles developed after mobs turned on television crews and press photographers

France’s first gay marriages could happen as early as June after parliament gave final approval to the country’s most controversial social legislation for three decades.

Thousands of riot police, equipped with water cannon and tear-gas, deployed in central Paris in expectation of trouble from hard-right and fundamentalist Catholic groups.

Late last night a group of 200 hard-right youths, wearing surgical masks and leather gloves, besieged riot police lines last night after a peaceful demonstration of 5,000 people broke up on Les Invalides in central Paris.

They tried to force their way towards ministry buildings but were forced back by tear-gas sprays. Running battles developed after mobs turned on television crews and press photographers.

The National Assembly voted by 331 to 225 to accept a slightly amended text of the gay marriage law passed by the upper house, or Senate, earlier this month. If the law survives, as expected, a centre-right challenge in the Constitutional Council, it could be signed into law by President François Hollande by the end of May.

The Justice Minister, Christiane Taubira, told parliamentarians last night that she expected the first French gay marriages in the coming weeks. "We believe that the first weddings will be beautiful and that they will bring a breeze of joy," she said.

"Those who are opposed to them today will surely be confounded when they are overwhelmed by the happiness of the newlyweds and their families," she added.

Opposition to gay marriage has mobilised the French right, from moderate conservatives to neo-Nazis. The movement has drawn strength from the unpopularity of President Hollande and the anger of right-wing voters at losing the presidential election almost exactly a year ago.

It has also revealed sincere doubts about the morality of gay marriage, and the adoption of children by gay couples, which have gone beyond the normal boundaries of left and right. But despite the violent protests, 60 per cent of French people continue to support the principle of marriage for homosexuals. France would be the 14th country to adopt such a law. A last-ditch protester, dressed all in pink, attempted to unfurl an anti gay-marriage banner in the National Assembly just before last night's vote. The assembly president, Claude Bartolone, ordered security staff to "remove the enemies of democracy".

Politicians on both the left and the right have grown alarmed by the increasingly confrontational tactics and hysterical language of small sections of the protest movement.

Mr Bartolone, the assembly speaker, received a death threat in a letter containing gunpowder on Monday. Far-right thugs have led a series of attacks on gays and gay bars, and members of the government have been bombarded with insulting and threatening mail accusing them of being part of a "Gaystapo".

The centre-left newspaper Libération celebrated the expected approval of the law by filling yesterday morning's edition, inset, with graphic full-frontal and rear male gay pin-ups.