Liberal Democrat MP Christine Jardine feels bad for Change UK after six of its members abandoned the party.
She told talkRADIO’s James Whale there was clearly “internal division” behind the split.
"I feel bad for them, they all left the party, that was difficult," she said.
“They have tried to do something quite difficult and unique in British politics and unfortunately today they’ve decided to go their different ways."
She added: "I think we’ll all just have to allow them over the next few weeks and months to re-establish what direction they want to go in.”
Ms Jardine said she’s willing to work with the defecting MPs, but said that is a “decision for them”.
“The old tribal two-party system, it’s been shown clearer than ever before through Brexit that it has to be changed.
“Any of those politicians, individuals or groups that want to help us work to change that and crucially, to remain in the European Union, we will work with them.”
Anna Soubry was announced as the new leader of Change UK yesterday after former leader Heidi Allen left the party.
She was one of six MPs to leave, along with along with former Labour members Chuka Umunna and Luciana Berger.
The said they were leaving so they would “be best placed to work cross party and respond flexibly”.
Change UK failed to win a single seat in the European elections last month.