The Independent Group formed by breakaway ex-Labour and Tory MPs has become a fully-fledged political party and will fight the European elections.
The new party, named Change UK - The Independent Group, will stand on a pro-EU platform calling for a second referendum.
They claim to have had more than 3,700 applications from people wanting to stand as Change UK candidates in the March 23 poll.
Some 70 candidates will be fielded by the party after it completed the registration process with the Electoral Commission.
Change UK's interim leader Heidi Allen said: "This is a fight for Britain's voice in Europe - and we have been overwhelmed by the thousands of people wanting to roll up their sleeves and join our campaign from every walk of life and every corner of the country.
"Change UK - The Independent Group have a clear message in the European elections: we demand a People's Vote and, if it is held, all our MPs will campaign to remain in and reform the European Union."
The party will launch its election campaign on April 23.
