David Cameron has slapped down maverick backbencher Nadine Dorries after she floated plans to campaign for election on a Tory-Ukip ticket.
Ms Dorries revealed she intends to talk to her local party about the possibility of standing as a joint candidate in 2015. Other Tory Eurosceptics could also seek Ukip's endorsement to prevent Nigel Farage's party standing against them, she suggested.
But the Prime Minister insisted the Conservative Party "doesn't do pacts and deals" and is set to win outright at the general election.
Asked about the comments during a press conference at the UN, Mr Cameron said: "The Conservative Party doesn't do pacts and deals. We are set to win the election outright. That is our aim and that what we will deliver."
Ms Dorries, who has only recently had the Tory whip restored after an unauthorised trip to the jungle for I'm A Celebrity... Get Me Out Of Here!, said the move was aimed at "healing the rift on the right" to block a Labour return to power.
She told BBC News: "Many of us think it's important that the right unites and it's almost a first step to a rapprochement between the Conservative Party and Ukip."
Such a move would appeal to Tories who "have some synergy" with Ukip on issues like Europe, opposition to gay marriage and support for grammar schools, the Mid Bedfordshire MP said.
"It's really about stopping the Labour Party taking power and keeping hold of good Eurosceptic Conservatives in Parliament," she added.
"I am a Conservative and my re-adoption would be by a Conservative Party. It's not being adopted by Ukip, it's just seeking Ukip endorsement so that they don't put a candidate up against you at the next election."
She added: "I'm not actually saying that people should change their allegiance from Conservative to Ukip - to the contrary actually, it's the opposite. I'm saying to keep Conservative MPs in Parliament and to stop the left, the Labour Party, getting back into power in 2015 we need to look at imaginative ways."