The PM spoke of “areas where we want to achieve the same goals in the same ways” in a passages which may have heralded the Brexit deal she was cooking up. 

Last night it emerged that Downing Street is planning a future “alignment” of UK regulations with Brussels in key areas which could impact on the thorny Irish border issue. 

Under the proposals Britain would independently continue to ensure that there is little or no divergence on issues related to the Good Friday Agreement and running of a smooth crossing. 

The UK and EU looked on course for a deal on those terms that would have unlocked trade talks until the unionist DUP erupted in rage late in the day, scuppering progress. 

DUP leader Arlene Foster spoke on the phone to Theresa May and refused to sign up to the pact following triumphalism from Dublin and a secessionist threat from Nicola Sturgeon. 

The SNP chief, along with London Mayor Sadiq Khan and Welsh first minister Carwyn Jones, all questioned why Northern Ireland was apparently receiving a special deal they were not. 

In reality, it is understood the Government’s plans would have encompassed the whole of the country equally so as not to undermine the territorial integrity of the UK. 

British officials have blamed the chaos on Dublin’s actions including the disastrous leaking of an earlier, rejected form of the agreement to its state broadcaster.

In her speech, delivered on September 22, the PM said: “Now in any trading relationship, both sides have to agree on a set of rules which govern how each side behaves.

“So we will need to discuss with our European partners new ways of managing our interdependence and our differences, in the context of our shared values.

“There will be areas of policy and regulation which are outside the scope of our trade and economic relations where this should be straightforward.

“There will be areas which do affect our economic relations where we and our European friends may have different goals; or where we share the same goals but want to achieve them through different means.” 

Tellingly, she added: “And there will be areas where we want to achieve the same goals in the same ways, because it makes sense for our economies.

“And because rights and obligations must be held in balance, the decisions we both take will have consequences for the UK’s access to European markets and vice versa.” 

Mrs May is expected back in Brussels as early as tomorrow as she attempts to patch up divisions with the DUP, which is propping up her Government, and seal a sufficient progress agreement with the EU. 

Last night both the PM and the EU Commission president Jean-Claude Juncker said they were confident a deal can still be reached which would allow EU27 leaders to trigger trade talks next week.