France's constitutional court has ruled that mayors cannot refuse to carry out same-sex marriages.
The ruling comes a month after seven mayors contested France's new law allowing for gay marriage. The mayors say it should have allowed local authorities to opt out on the grounds of freedom of conscience.
In France, marriages can only be made official by city authorities, though many couples celebrate religious weddings, too.
While the French Constitution allows for expressions of freedom of conscience, the court rejected the mayors' arguments and ruled that the disputed part of the legislation was constitutional.
The law allowing gay marriage exposed deep divisions in French society, prompting big protests for and against such unions.