Several thousand people demonstrated against Britain's plan to leave the European Union in London and other cities on Saturday.
United under the slogan "March for Europe" the demonstrators moved through London, starting at Hyde Park and ending in front of the British parliament building, where a debate about a second EU referendum is set to be held on Monday.
A second referendum is being discussed due to a petition, which was submitted before the referendum to exit the EU, that gathered more than 4 million signatures.
The petition demands a another referendum be held if the first received less than 60 per cent voting in favour of leaving the EU with a voter turnout of less than 75 per cent.
Britain decided in June to exit the European Union with a 52 per cent majority. Voter turnout was 72 per cent.
The British government has already announced that it doesn't plan to hold a second referendum, saying the will of voters has to be respected.