Theresa May will today pledge a clean break with the European Union, ruling out “half-in, half-out” or partial membership.
In what will be widely interpreted as the foundations of a so-called hard Brexit, the prime minister will promise to pursue a “new and equal partnership”.
She will add the UK will not seek associate membership, “a model already enjoyed by other countries” or to “hold onto bits as we leave”.
Her words will fuel speculation – rife over the weekend – that the UK Government is planning to take Britain out of the single market and customs union.
The pound hit its lowest level for more than three months in response to the claims.
Billed as a speech to set out her negotiating objectives, Mrs May will need to provide a certain amount of detail or face calls for clarification afterwards.
She is expected to insist the withdrawal negotiations are about more than determining the UK’s new relationship with the EU, but also an opportunity to “step back and ask ourselves what kind of country we want to be”.
She will claim she wants the UK to emerge from the period of change “stronger, fairer, more united and more outward-looking than ever before”, and a “secure, prosperous, tolerant country” that attracts international talent, pioneers and innovators.
Mrs May will add: “I want us to be a truly global Britain – the best friend and neighbour to our European partners, but a country that reaches beyond the borders of Europe too.”
But she will also make clear there are to be no half measures when it comes to Brexit.
“We seek a new and equal partnership,” she will say. “Not partial membership of the European Union, associate membership of the European Union, or anything that leaves us half-in, half-out.
“We do not seek to adopt a model already enjoyed by other countries. We do not seek to hold on to bits of membership as we leave.
“The United Kingdom is leaving the European Union. My job is to get the right deal for Britain as we do.”
In a message to the rest of the EU, Mrs May will argue it remains in Britain’s interests for the EU to succeed and repeat the point the UK is not leaving Europe.
And she will claim: “Our vote to leave the EU was no rejection of the values we share. The decision to leave the EU represents no desire to become more distant to you, our friends and neighbours.”
