The former Tory MP was responding to Prime Minister Theresa May’s proposed “backstop” customs system for Northern Ireland, which could see Britain remain in a “temporary customs arrangement” after the Brexit transition.
Mr Portillo warned that Remainers are creating an “unsatisfactory” deal in order to trigger a second Brexit referendum.
Speaking on BBC This Week, Mr Portillo said: “The Prime Minister has been surrounded by Remainers.
“I think there has been a conspiracy to arrive at this situation.
Brexit news: Michael Portillo warned Theresa May is “surrounded” by Remainers
The Prime Minister has been surrounded by Remainers
“We’ve allowed the Northern Ireland situation to dictate the entire policy.
“And we arrive at a situation which everybody knows is unsatisfactory and I think that is part of the plan as well because the Remainers believe that it will be so unstable that it will trigger a reconsideration before long.”
He added: “To call it incompetence is too kind. I think this has been a conspiracy.
“All the senior civil servants are Remainers, about half the cabinet are Remainers – probably more than half the Conservative Parliamentary Party are Remainers.
“The British people voted to Leave but they continued to take this preterition view that the British people had got it wrong and shouldn’t be allowed to do something which was going to do them so much damage.”
On Friday, a spokeswoman for Prime Minister said: “There isn’t going to be a second referendum.”
Mrs May’s backstop draft sets out a blueprint for a temporary customs partnership if the technology for a “frictionless border” is not prepared in time for the end of the Brexit transition period in December 2020.
Mr Portillo warned the Brexit negotiations would have been over if David Davis had resigned over the Brexit backstop.
He said: “I think the government would have fallen apart and there would have been no possibility whatsoever of continuing even our meagre negotiating position as we have it now because we would essentially be without government.”
Mr Davis had threatened to resign after the Brexit backstop option was published on Thursday did include a time limit despite government disagreements.
Mrs May confirmed that a temporary “backstop” arrangement to prevent a hard border between Northern Ireland and the Republic would be time-limited.
The draft arrangement is set to continue no longer than December 2021 – a year after the transition period, which ends on December 2020.
The document said: “The UK is clear that the temporary customs arrangement, should it be needed, should be time-limited, and that it will be only in place until the future customs arrangement can be introduced.
“The UK is clear that the future customs arrangement needs to deliver on the commitments made in relation to Northern Ireland.
“The UK expects the future arrangement to be in place by the end of December 2021 at the latest. There are a range of options for how a time limit could be delivered, which the UK will propose and discuss with the EU.”
Guy Verhofstadt, the European Parliament’s chief Brexit negotiator, also criticised the Brexit backstop option.
He tweeted: “Difficult to see how UK proposal on customs aspects of IE/NI backstop will deliver a workable solution to avoid a hard border & respect integrity of the single market/customs union.
“A backstop that is temporary is not a backstop, unless the definitive arrangement is the same as the backstop.”