Thousands of people have joined the march to Parliament, on the second anniversary of the UK voting to leave the EU.
Those behind the protest, People’s Vote, are aiming to put pressure on Theresa May and the Government saying Brexit is “not a done deal” and people must “make their voices heard”.
The protest is part of what some campaigners are calling “a summer of action” against the government.
Protestors have gathered in their thousands two years on from the UK voting to leave the EU by a margin of 51.9% to 48.1% in a referendum held in 2016.
Organisers of the People’s Vote march expect tens of thousands of people to show their support for a referendum on the final Brexit outcome.
Marchers will descend on Parliament Square, where speakers will include Liberal Democrat leader Sir Vince Cable, Tory former minister Anna Soubry, Labour’s David Lammy and Green co-leader Caroline Lucas.
Sir Vince is expected to say Brexit is not a “done deal” or inevitable and can be stopped.
“Parliament is fiddling at the margins while the country slowly burns,” he is expected to warn as he calls on the Government to vote on the deal, or no deal, with the option of staying in the EU.
The CER estimate of a 2.1% smaller economy than if the UK had voted to remain in the EU is equivalent to a knock-on hit of £23 billion a year to the public finances, some £440 million a week.
CER deputy director John Springford said: “Two years on from the referendum, we now know that the Brexit vote has seriously damaged the economy.”