Opponents of the law say France is not ready to legalise adoption for same-sex couples, and polls show that the country is sharply divided on the issue, despite French parliament passing it into law today.
France has become the 14th country to legalise same-sex marriage following New Zealand last week.
Thousands of police mobilised ahead of the vote, preparing for dueling protests around the National Assembly building and along the Seine River. At least one spectator was ejected from the gallery.
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Two pilots have been arrested on suspicion of being under the influence of alcohol as they prepared to fly from Scotland to the New York.
Two teenagers have been arrested on suspicion of drugs offences following the death of a 17-year-old youth who collapsed at Leeds Festival.
Theresa May will gather Cabinet ministers together on Wednesday to discuss her plans for Brexit.