The leader of Change UK, Heidi Allen, has said her party could merge with with the Liberal Democrats, appearing to put her at odds with Chuka Umunna.

On Saturday, Umunna, a Change UK MP and spokesman, said the Independent Group should form a pact not to stand against Lib Dems in the next general election.

But Allen, who left the Conservatives to join two other breakaway Conservative and Labour MPs to form the pro-remain group, said she would go “one step further”.

Speaking to BBC Radio 5 Live, she said: “I would like us to be in the same vehicle.” Asked if she meant the same party, Allen replied: “Yeah, probably, I don’t know. This partisan thing completely passes me by and when I look across Europe, they seem to do pretty well with coalitions.

“I don’t know what the format will be, but will we be singing from the same hymn sheet? I would hope as a collective, let’s call us a collective, somewhere in the middle with other likeminded colleagues. I don’t think it’s sensible to be too prescriptive at the moment.”

Allen said to be a “real insurgent force”, the alliance needed to be “brand new” rather than a larger Liberal Democrat party.

Last week, she admitted she had threatened to quit in an internal row over tactical voting to maximise the pro-remain challenge to Nigel Farage’s Brexit party.

But on Sunday she indicated all MPs within the party were moving towards a closer relationship with the Liberal Democrats.

“I think we are sensible enough to know we can’t do it on our own,” she said. “Are we at different stages on the continuum? Of course we are, because everybody’s different. “But do we all agree that the long goal is something centrist together? Then, yes, we are all on that same path.”

Allen said she believed more Tory MPs could desert the party if Boris Johnson became prime minster, while Labour MPs may also defect if Jeremy Corbyn continued to refuse to commit to a second referendum.

Umunna said on Saturday he thought a pact with the Liberal Democrats would be “sensible”, adding: “I personally don’t think we should be competing at a general election.” He cited a pact that the then Liberal party held with the Social Democrats in the 1980s.

On Sunday, ahead of the European election results, Umunna thanked party workers but appeared to accept Change UK was facing humiliation in the polls. “Whatever the results are tonight everyone can be proud,” he said in a video message to the party’s supporters.