Thousands of British activists have pledged to take part in what they called the largest demonstration against the new U.S. President Donald Trump in the country.

The event, organized by the Stop Trump coalition, will gather activists, lawmakers, and trade unions on Monday. It is expected to draw at least 10,000 people.

“Our hope is that this mass movement can swing public opinion on a range of issues in a way that progressives have never managed before, and on issues on which we have been losing for decades,” said the group’s spokesman.

Unison, GMB and the National Union of Students have also supported the rally.

Recently, nearly 1.8 million people signed a petition to scrap Trump’s planned state visit to the UK. The move was later rejected by the British government.

“The planned state visit should clearly be cancelled and the invitation binned. It’s no wonder that almost 2 million people have signed a petition against the visit, and I’m proud that so many of my constituents have joined that call,” said Caroline Lucas, a Green Party MP who was attending the event.

Trump’s decision to ban Muslims of 7 countries from entering the United States has received backlash across the world.