DUP leader Arlene Foster has said Theresa May will now have a better understanding of Brexit's "challenges and opportunities" following her two-day trip to the north, including a visit to the border.
As the Tory leader returned to London yesterday afternoon, the former first minister said Mrs May's speech in Belfast yesterday had a "welcome theme and tone".
"The support for the union as well as the clear statement that there can be no hard border nor new internal borders in the United Kingdom was good news," Mrs Foster said.
In her address at the Waterfront Hall, Mrs May claimed the EU's 'backstop' proposal breeched the Good Friday Agreement, as it would "dislocate" Northern Ireland from Britain.
But Sinn Féin president Mary Lou McDonald accused Mrs May of "coming to pick a fight with Ireland and to pick a fight with the European Union".
Speaking after meeting the Tory leader, the Dublin Central TD said: "We were told that the British prime minister came to Ireland to listen and to reassure – it is clear that she is not listening to community and business interests and seeks only to reassure the DUP."
Mrs McDonald claimed Mrs May had "set aside" an agreement made with the EU in December by rejecting Brussels' 'backstop'.
"Theresa May claims to want to avoid a hard border in Ireland, while pursuing a policy that will deliver a hard border," she said.
SDLP deputy leader Nichola Mallon described the prime minister’s speech as "underwhelming" and "void of any substance"
"For all of her talk of genuinely listening to the concerns of the people of Northern Ireland, a significant portion of the prime minister’s speech sounded like it was drafted by the DUP," the North Belfast MLA said.
Alliance deputy leader Stephen Fary said Mrs May need to "listen to all voices across the community in a balanced way".
Ulster Unionist leader Robin Swann said Northern Ireland was "being offered no certainty on Brexit".
Meanwhile, speaking in Brussels, tanaiste Simon Coveney said some elements of Downing Street's recent white paper on Brexit would be the basis of agreement but others "might not be workable".
"We want to de-dramatise some of these things, which are the basis of exaggeration and headlines across media outlets, and get down to a focused negotiation to try to work out what in the white paper can be accommodated and can be the basis of agreement and in what areas do we need new thinking to ensure that the EU's interests are protected while also negotiating a fair deal for Britain," he said.
