Iain Duncan-Smith has claimed the EU will be in "no rush" to do a trade deal with the UK during the implementation period.
The former Conservative leader has said the withdrawal deal proposed by Theresa May won't "bring back control" of our borders or laws.
Talking to Julia Hartley-Brewer on talkRADIO, Duncan-Smith said the EU has got the UK exactly where they wanted, by "trapping" the country in a customs union to prevent the UK from being competitive.
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In reaction to the government's withdrawal proposals, he said we would find ourselves "back in for a period" once we had left on March 29.
“Whatever happens we are officially leaving on March 29," he said.
"We officially leave, then the problems really begin because with the implementation period which we had agreed on the basis of that and we would go, we will actually find ourselves back in for a period, which is unspecified, there are real problems.
"I haven’t read the full 500 page affair, I’ve been dipping through it last night and I’ll do more work on it, as far as I can see, the issues on this are: at the end of this implementation period if there has not been a trade agreement signed, the UK has now accepted that it will, in essence as the UK, would stay in the customs union, and Northern Ireland won’t only just be in the customs union, but Northern Ireland will be forced essentially to remain within the single market.
"In essence it means there will have to be some kind of check between Northern Ireland and the UK because they will be in a system that the rest of the UK won’t be."
President of the European Council, Donald Tusk, holds the draft withdrawal agreement. Image: Getty
"The real problem is there is no pressure on the EU to do a trade deal early, they’ve got the UK exactly where they wanted and that is to say they don’t need to rush, as while the UK is trapped in the customs union we can’t really be competitive which is their greatest fear," he warned.
"Secondly they still retain a measure of control.”
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"The court of justice is absolutely clear with anything to do with European law and regulations will apparently be supreme, now I voted to take back control of our laws, borders and our money, and this means we won’t be taking back control of our borders unless we do a deal, and unless we do a proper trade deal we won’t be taking back our laws.”