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It had been billed as a march to give confident voice to those who want the Brexit debate put back to the people, but as crowds set out on the People's Vote march, the nervous chatter was how the MP Oliver Letwin's amendment might be their only hope.

The mood: resolute, anxious, even pessimistic.

This long-planned event provided a noisy soundtrack to government attempts to bring the Brexit argument to an end before the march reached its destination.

Pictures from inside the Palace of Westminster were relayed to the vast crowd watching on a big screen erected on Parliament Square outside.

And then the moment when it was clear there would be no Brexit deal today. It was less a moment for rejoicing, more a sense of relief.

The long march that the protesters hope will lead from one people's vote to another will go on.

What the final destination looks like, for those on all sides of the argument, that remains frustratingly unclear.