The DUP's Brexit spokesman, Sammy Wilson, has said that the issue of the Irish border has been used as an "excuse" to "delay or stop" Brexit.
The politician claimed ongoing negotiations over how to stop a hard border forming in Ireland was a "strategy" to keep the UK inside the European Union.
"This is not about a real problem.This is about a strategy to keep the UK inside the EU," Mr Wilson told Julia Hartley-Brewer.
"I can't understand why the Prime Minister continues to try and address a problem which she must know is not a real problem."
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The Prime Minister has said she is willing to extend the length of the post-Brexit transition period in an effort to solve the current impasse over the Irish border.
"An extra decade, an extra century will not make a difference to this issue," Mr Wilson added.
"Here's the strange situation then, if there's a no deal there'll be no hard border, but if there's a deal, there's every likelihood of a hard border.
"I thinik it really exposes just the nature of what this is all about. This is about finding an excuse to either delay or to stop the United Kingdom leaving the EU."