The South Cambridgeshire MP said the UK's politics is 'broken'.
Lib Dem leader Jo Swinson hopeful other pro-Europeans will follow suit.
Lib Dem leadership candidate says Chuka Umunna and others need to earn "trust" of party membership.
Leader Heidi Allen and Chuka Umunna are among those to quit.
The Remain alliance could be on after all.
Lib Dem leader says his party is "on the side of the angels" as he aims to go out with a bang at the European elections.
The new party said the BBC has "got a couple of big calls wrong".
"We even offered to blur Heidi Allen’s face."
Boris Johnson's sister stands for pro-Remain party created by Independent Group of MPs.
Candidates for the Independent Group of ex-Labour and Tory MPs will have a blank space next to their names, instead of the party emblem.