Theresa May’s proposed new economic partnership with the EU “will not work”, the head of the European Council has said.
Donald Tusk said the plans risked undermining the EU’s single market.
He was speaking at the end of an EU summit in Salzburg where leaders of the 27 remaining member states discussed Brexit.
Mrs May said her proposals were the “only serious credible” way to avoid a hard border in Northern Ireland.
She said she had held “frank” talks with Mr Tusk, adding: “Yes, concerns have been raised and I want to know what those concerns are.”
There was “a lot of hard work to be done”, she said, but added that the UK was also making preparations in case no deal could be reached.
Mrs May reiterated that she would not accept the EU’s “backstop” plan to avoid a hard border in Northern Ireland, and said the UK would shortly be bringing forward its own proposals.
