The Sinn Fein president and Prime Minister Boris Johnson have spoken by phone to discuss Brexit.
Mary Lou McDonald spoke to Mr Johnson at Sunday lunchtime.
Ms McDonald’s office said she reminded the Prime Minister of his obligations under the Good Friday Agreement and told Mr Johnson that there could be no unionist veto on protections for Ireland.
“Ireland did not consent to Brexit,” Ms McDonald said following the call.
“The people of the north voted to remain.
“This afternoon I reminded the British Prime Minister of this and of his obligations under the Good Friday Agreement to ensure no hardening of the border.
“I told the Prime Minister that any deal agreed must have legal and enduring guarantees that deliver for Ireland.
“There can be no customs border on our island. Our livelihoods, our economy and our peace must be protected.
“I also sought confirmation that there would be no veto gifted to DUP Brexiteers on protections for Ireland – such a position would be intolerable.
“The next week will be critical. Ultimately we need a deal that delivers for Ireland. Prime Minister Johnson and I agreed to stay in contact and continue to engage on these and other important issues.”
It’s understood that negotiations in Brussels over Brexit have been intense over the weekend, as both sides enter the proverbial tunnel to decide on how the UK will leave the EU on October 31.