Update 1pm: Theresa May has lashed out at internal Conservative critics of her plans for the border, accusing them of being ready to "betray" the people of Northern Ireland and the Republic.
And she sent a message to Brussels that the EU must change its negotiating position in response to the plans for a post-Brexit relationship which she drew up at Chequers.
The British Prime Minister was speaking in Belfast as ministers from the remaining 27 EU states met in Brussels for a briefing from chief Brexit negotiator Michel Barnier on the plan set out in Mrs May’s White Paper last week.
In a sign of growing concern in Dublin about the prospect of a hard Brexit, Taoiseach Leo Varadkar suggested Ireland could close its airspace to UK planes if Britain seeks to ban EU ships from fishing in its waters.
In her first major Brexit speech since the wave of ministerial resignations which followed her Chequers deal, the Mrs May described the White Paper proposals as “a significant development of our position … a coherent package”.
And she said: “It is now for the EU to respond – not simply to fall back on to previous positions which have already been proven unworkable, but to evolve their position in kind.
“And, on that basis, I look forward to resuming constructive discussions.”
She sent a blunt message to supporters of a hard Brexit, like Jacob Rees-Mogg, who have argued that the UK should simply declare it will impose no checks at the Irish border after EU withdrawal and leave it to Brussels to decide whether to require the Republic to erect barriers.
“This issue arises because of a decision we have taken,” she said. “We can’t solve it on our own, but nor can we wash our hands of any responsibility for it, so we must work together to solve it.”
The UK has a “duty” to ensure that its borders with neighbouring countries function smoothly, she said, adding that this was “a particular challenge” in Northern Ireland.
“The protection of the peace process and upholding our binding commitments in the Belfast Agreement are grave responsibilities,” she said.
“Not to seek a solution would be to resume our career as an independent sovereign trading nation by betraying commitments to a part of our nation and to our nearest neighbour.”
And she took a swipe at former foreign secretary Boris Johnson’s claim – repeated in his resignation speech to the Commons on Wednesday – that technological solutions could be used to avoid the need for infrastructure at the border.
“No technology solution to address these issues has been designed yet or implemented anywhere in the world, let alone in such a unique and highly sensitive context as the Northern Ireland border,” she said.
- Press Association
Theresa May has insisted she will not accept any Brexit deal that treats the North differently to the rest of the UK.
Ms May has also shot down suggestions the six counties could stay in the single market.
Notion of a hard border in Ireland after #Brexit is "inconceivable" and "alien", says PM Theresa May during speech in Northern Ireland https://t.co/4gKrjtWXdQ pic.twitter.com/NbTnJuaYJg— BBC News (UK) (@BBCNews) July 20, 2018
She says she wants a frictionless border when Britain exits the EU.
The British Prime Minister's speech in Belfast follows 24 hours experiencing life for people in the North first hand.
She has promised not to forget about them in negotiations: "Any agreement we reach with the EU will have to provide for the frictionless movement of goods across the Northern Ireland border.
"Equally clear, we could never accept that the way to prevent a hard border with Ireland is to create a new border within the United Kingdom.
"It would not be showing parity of esteem and just and equal treatment of the Unionist community in Northern Ireland to cut their part of the United Kingdom off from the rest of the UK."
Theresa May's challenge to EU negotiators: improve your proposals on Northern Ireland, trade and borders after #Brexit - rather than "fall back onto previous positions that have been proven unworkable" https://t.co/4gKrjtWXdQ pic.twitter.com/xA1OO0SgJb— BBC News (UK) (@BBCNews) July 20, 2018
British Prime Minister Theresa May is speaking in Belfast addressing the issue of Brexit.
DUP leader Arlene Foster say she is hopeful a deal can be reached on Brexit between the UK and the EU.
Ms Foster has met with Theresa May to discuss the issue, during Ms May's two-day visit to the North.
The British Prime Minister is expected to outline her Brexit vision in a speech in Belfast later today.
The DUP's leader says it is also in the interest of the EU to secure a deal with the UK.
"Sometimes we get fixated at looking at the United Kingdom's position in all of this but don't forget that the European Union needs a deal with the United Kingdom as well because they sell a lot of goods into the UK and a lot of people come from the European Union into the UK," said Ms Foster.
Delighted to welcome the Prime Minister to Fermanagh & S. Tyrone - the most western constituency in the United Kingdom. Great discussion earlier with people who live and work on the border. . . Having dinner on the banks of Lough Erne - that’s RoI just across the water. pic.twitter.com/TF0GhX7SNz— Arlene Foster (@DUPleader) July 19, 2018
"So there needs to be a deal for both sides. I hope that there's a realism around all of that and a willingness to do business between the European Union and the United Kingdom."
Later today, Ms May will again insist that she will not accept anything that treats the North differently from the rest of the UK.
But Sinn Féin's vice-president Michelle O'Neill thinks Ms May's government is not handling the situation very well.
"We can't withstand being outside the Customs Union and the single market," said Ms O'Neill.
Speaking to media earlier. 2yrs after Brexit Ref Teresa May finally visits a border constituency. There is no good news in Brexit. Cast iron guarantees, legal certainty are required. Our rights, economic prosperity and services won’t be trampled on for their political expediency pic.twitter.com/ZKvZAWwEDO— Michelle O’Neill (@moneillsf) July 19, 2018
"Theresa May needs to understand that we will not be collateral damage for her own reckless Tory agenda.
"We will not stand idly by and allow her to put her own political expediency over the rights of citizens here."
Meanwhile, the Tánasite and Foreign Affairs Minister Simon Coveney is meeting with the EU's chief Brexit negotiator in Brussels.
He will discuss the current state of play in the negotiations with Michel Barnier.
Mr Coveney is also attending the EU's General Affairs Council - where he says he will stress the need for progress with our EU partners.
Looking forward to meeting @MichelBarnier in Brussels tomorrow - we will focus on what’s important - finalising the Withdrawal Agreement and protecting Ireland. No Withdrawal Agreement without an Irish Border Backstop, as agreed by UK. https://t.co/1DmE95y87O— Simon Coveney (@simoncoveney) July 19, 2018
Theresa May is to tell the European Union to “evolve” its stance on Brexit, warning that previous positions are “unworkable”.
The British Prime Minister will use a speech in Belfast on today to reiterate her refusal to contemplate any backstop deal that treats the North differently from the rest of the UK.
Speaking at the city’s Waterfront Hall, she is due to say that any such deal would go against the Good Friday Agreement, which brought peace to the North 20 years ago after decades of conflict.
Mrs May will say that following the publication of the Government’s white paper agreed at Chequers, it is “now for the EU to respond”.
She will add: “Not simply to fall back on to previous positions which have already been proven unworkable. But to evolve their position in kind.
“And, on that basis, I look forward to resuming constructive discussions.”
The EU’s other 27 states will have a chance to examine and respond to the white paper when its General Council of ministers meets in Brussels on Friday morning.
They will also receive an update on negotiations from the European Commission’s chief negotiator, Michel Barnier.
The Irish border issue is one of the most disputed parts of the Brexit negotiations.
In the event of a hard no-deal Brexit, the EU wants a backstop that would effectively create a border down the Irish Sea between the island of Ireland and Great Britain, something Mrs May has repeatedly opposed.
The UK Government insists that any backstop position should include the UK as a whole.
I enjoyed meeting @MichelBarnier , discussing the progress we have made, and the outstanding issues to resolve across the Withdrawal Agreement and the Future Framework. I’m looking forward to stepping up the pace and energy in our negotiations. https://t.co/7v0D91sS8I— Dominic Raab (@DominicRaab) July 19, 2018
Her speech comes the day after new Brexit Secretary Dominic Raab headed to Brussels for the first time to take part in talks with Mr Barnier.
Mr Barnier told reporters on Thursday that it was “a matter of urgency to agree a legally operative backstop”, saying: “We need an all-weather insurance policy.”
Mr Raab said that he was looking forward “with renewed energy, vigour and vim” to seeing the detail of the White Paper hammered out after a gruelling Cabinet conclave at Chequers.
Brexiteer Commons Leader Andrea Leadsom put some pressure on Mrs May’s plan, saying the EU must be told the Chequers blueprint, which has divided the Conservative party, is the “final offer” rather than an opening gambit.
However she also admitted quitting without an agreement would not be an “optimal solution”.
UK Foreign Secretary Jeremy Hunt, meanwhile, insisted the deal is “absolutely alive” despite the Government being forced to make concessions to Brexiteers.
Mrs May will again refuse to countenance any backstop that creates a divide between the North and the rest of the UK.
“The economic and constitutional dislocation of a formal ‘third country’ customs border within our own country is something I will never accept and I believe no British prime minister could ever accept.
“And as they made clear this week, it is not something the House of Commons will accept either.”
As the EU warns member states to increase preparations for no deal, the British prime minister is also due to insist that an agreement can be reached with Brussels “that works in our mutual interest”.
She will say the deal will put the UK on the way to “a prosperous future, protecting jobs and boosting prosperity” at the same time as honouring the 2016 referendum result, adding: “I am passionate about that brighter future and the possibilities that are within our grasp.”
Amid the ongoing power-sharing impasse at Stormont, Mrs May is meeting the five main political parties on her two-day visit to Northern Ireland, which included her first visit to the Irish border since the Brexit referendum.
She held talks with her Westminster confidence and supply partners, the DUP, on Thursday evening, an engagement that included a private dinner with leader Arlene Foster and deputy leader Nigel Dodds in Co Fermanagh.
Mrs May also held talks with an SDLP delegation.
On Friday morning she will meet Sinn Féin, the Ulster Unionists and Alliance Party.
Ahead of the meeting on the outskirts of Belfast, Sinn Féin President Mary Lou McDonald heavily criticised Mrs May’s handling of the Brexit process.
“The British government’s Brexit chaos has been marked by prevarication and stalling, ever-changing positions and broken agreements,” she said.
“This situation is intolerable and unacceptable.”
Victims of the Troubles angered at a lack of progress in implementing new mechanisms to deal with the legacy of the conflict are due to protest against Mrs May’s visit to Belfast.
- Press Association