British prime minister Theresa May is to visit Belfast on Tuesday to deliver a Brexit speech and meet businesspeople.
Mrs May is due to reiterate the British government's commitment to avoiding a hard border in Ireland. She is also expected to explain why she is now seeking an alternative to the backstop that she had previously agreed with the European Union.
Her speech in Belfast is taking place as the British government seeks to conduct new negotiations with the EU about the EU-UK withdrawal deal which was comprehensively rejected by the House of Commons last month.
Mrs May originally urged political and business leaders in Northern Ireland to support her Brexit deal but after it was defeated in the House of Commons by 432 votes to 202 she then moved to try to find an alternative to the backstop.
The British Labour Party's Brexit spokesman Sir Keir Starmer who met business people, trade unions and the SDLP and Sinn Féin in Belfast on Monday, said he had detected "great anxiety" in Northern Ireland after Mrs May "voted against the backstop that she negotiated".
"That has raised levels of anxiety about a no deal outcome," he told The Irish Times on Monday.
And while Labour leader Jeremy Corbyn has opposed the backstop Sir Keir said it appeared that some form of backstop was now inevitable. He said: "We have got concerns with the backstop but we accept that a backstop is inevitable given that the prime minister has now run down the Article 50 clock and nobody credibly thinks that a new treaty arrangement with the EU is going to be agreed by January 1st 2021.
“So we have concerns about the backstop but we now recognise that a backstop is now inevitable.”
Sir Keir called on Mrs May to shift from her so-called red lines and to hold a House of Commons vote on a permanent customs union to help break the Brexit deadlock.
“I think the prime minister should reflect on what happened when she suffered that historic defeat. If you have red lines and then you are defeated by 230 votes you ought to rethink your red lines,” he said.
“If she doesn’t parliament will have to reassert itself and sooner rather than later parliament will have to choose between the credible options still left on the table,” he added.
“The prime minister has said that she wants an alternative to the backstop. She and her team and the EU have been looking for that alternative for more than 12 months and had there been an alternative the backstop would not have been agreed,” said Sir Keir.
“My concern is that the prime minister has raised an expectation about an alternative to the backstop that she can’t fulfil. She needs to then decide what to do, to decide whether she is going to try to come back and ram her deal through somehow, or agree with the majority in parliament who I believe would agree to a combination of a customs union and single market alignment,” he added.
“That would be far better for our economy and is the only credible way of ensuring there is no hard border in Northern Ireland,” he said.
Sinn Féin deputy leader Michelle O’Neill, who with party leader Mary Lou McDonald is this week due to meet Mrs May, said she made it clear to Sir Keir in Belfast on Monday that the backstop was “not open to renegotiation”.
"We are standing firm with the EU27 and Irish Government to ensure the backstop is protected and maintained," she said.
SDLP leader Colum Eastwood said he was encouraged by his meeting with the Labour MP. "Labour have a strong history in recognising the delicate position we find ourselves in here, as well as stepping up to assist us in the progress of maintaining peace. We hope this is a position they will take in any forthcoming Brexit votes," he said.
“The SDLP have been clear, we cannot allow the disarray in London to spill over and disrupt the lives of people here. The backstop must be banked,” added Mr Eastwood.
