Pro-Europeans said on Thursday they would hold a “march for change” rally against Brexit on July 20 in London.
The governing Conservatives are in the process of choosing a successor to Prime Minister Theresa May, with the result of the contest expected the week of July 22.
“As a new prime minister prepares to take office, grassroots organisations will gather in central London for one of the biggest pro-European rallies that the UK has seen,” the march organisers said.
“The march for change will put the proud and confident case for remaining in the EU. This will mark the start of a national fightback against a government seemingly determined to deliver a no deal or hard Brexit by October.”