After demonstrators spread sand on the pavement outside the embassy, a woman in a burkini and a child sat playing in it. Others wore bikinis as traditional French accordion music played in the background.
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Protestors carried placards with slogans such as "Burkini ban is racist" and "Islamophobia is not freedom".
Many spoke of their shock at a photograph widely published by British media this week which showed a headscarved woman, surrounded by police on a beach in Nice in the south of France, who had to remove a top garment.
"Yesterday when I saw the images of the woman on the beach I felt sick to my stomach," said Esmat Jeraj, one of the organisers.
"In terms of this event, it was a bunch of very frustrated, very angry women coming together to demonstrate that this was unacceptable and that something needed to be done."
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Rosalind Hayes, a 24-year-old student, said she had found the image "very resonant".
"It's just a concern, the increasing number of different curbs on people's ability to be in society without being controlled, going throughout Europe," she said, leaning on her bicycle.
A group of three women wearing black hoods over their heads and calling themselves the Sisters of Perpetual Resistance carried a placard saying "Liberte, Egalite, Sisterhood" - a reference to France's national motto.
"Clearly it's outrageous," said one of the trio, who declined to identify themselves.
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"I'm almost 60 years old, I've been fighting this shit all my life. Women should wear what they want to wear, where they want to wear it, without bloody men telling them what they should and shouldn't do."
Dozens of French towns and villages have banned beachwear that "conspicuously" shows a person's religion - aimed at the full-body Islamic swimsuit but which has also been used against women wearing long clothes and a headscarf.
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