Former Change UK leader Heidi Allen has spoken for the first time since leaving the party, saying she left over tactical voting in the European Elections.
She said: "It's more complicated than that but the party was still behaving in the ways of the party triumphing rather than that to protect the country".
When asked by ITV News Political Editor Robert Peston on whether she'd join the Lib Dems she said: "Never say never because they are shifting sands."
She told Peston on his Wednesday evening programme she understands why people might think she'd want to join the Liberal Democrat and added she has always wanted to put "the country first over party".
The Change UK party was formed in February by MPs who rejected the main political parties' stance on Brexit and other issues and defected from the Labour and Conservative party.
Ms Allen had been the party's leader and Chuka Umunna was spokesman, but they left the party on Tuesday, along with Luciana Berger, Gavin Shuker, Angela Smith, and Sarah Wollaston.
Rory Stewart, the International Development Secretary who confirmed his ambitions for the top job, said he can "comfortably pass" the first round of votes but his concern is the one after.
He said: "I've got enough votes to get through, the only question is can I get through the second or third rounds."
He also spoke out over Boris Johnson's leadership bid saying there was a "deeper problem" before adding: "Johnson cannot deliver Brexit by 31 October."
"If he is campaigning that he is going to get a different deal from Brussels he won't," he added.
When asked about Dominic Raab's comments saying as prime minister he would prorogue Parliament to force through a no-deal Brexit, Mr Stewart branded that as "illegal, unconstitutional and it would be undemocratic."
Tory MP, Theresa Villiers, said she has had very good conversations with Boris Johnson, Dominic Raab and Sajid Javid and isn't sure who she will be backing in the leadership race.
She said: "At the moment we don't know who the finalists of the candidates will be, for me actually getting more police on the beat and more funding for our schools are key issues that I'm asking all the candidates."
She continued: "We need to ensure that all the candidates have a good strong domestic agenda as well as preparing to ensure that we live up to our manifesto commitment to leave the European Union."
In terms of Brexit she said: "We cannot drag this out any longer. I think we've just got to get on with it."
Shadow Chancellor John McDonnell has said the decision on the second referendum will be determined during Labour's party conference.
He added: "There are large numbers of members well saying like me the obvious solution at the moment is to go back to the people because we have got."
"Every member wants a general election to get rid of this general election but if it's not likely then let's get back to the people on the referendum and at the same time any deal that does go back to the Parliament should go back to the people."