British prime minister Theresa May warns the EU to avoid the “unacceptable” demands in negotiations over Northern Ireland’s borders.

The prime minister will set out her case to other European leaders at a informal summit in Salzburg  this week, hosted by Ausrtian Presidency of the EU.

The reaction came after the EU top negotiator Michel Barnier suggested a shift in tone on his controversial “backstop” plan to avoid a hard border.

“We are ready to improve this proposal,” Barnier said.

Another key EU figure, European Council president Donald Tusk, said the UK’s plan for the Irish border “will need to be reworked“.