Brexit talks have been deadlocked over the so-called backstop - the fallback position that would be activated if a future EU-UK trade deal does not produce a solution that would prevent a hard border between Ireland and Northern Ireland.
With a Brexit deal nearing completion with Brussels, the PM is trying to secure the agreement of her cabinet to press on with finalising the terms for Brexit.
Ms McDonald was speaking to the media after it emerged that Leo Varadkar told UK Prime Minister Theresa May in a phone conversation that he was willing to consider proposals for a review clause in any backstop plan.
The DUP's Donaldson, whose party has repeatedly criticized Dublin's approach, said a no-deal Brexit would have serious consequences for Ireland's economy and he "can't understand why Irish Government seems so intent on this course".
The former Brexit secretary yesterday called on the government to publish the legal advice it has on the Irish border backstop.
A spokeswoman for the Irish Government said both leaders emphasised their commitment to avoiding a hard border and the need for a legally operable backstop.
But Brexit secretary Dominic Raab has reportedly demanded the backstop is time-limited, with Britain able to review it and pull out if it wants.
The Daily Telegraph reported on Monday that Brexit secretary Dominic Raab had taken a "hardline" stance on the border, insisting that the United Kingdom should have the right to pull out of the backstop via a review process after just three months.
Unemployment rate stays at 3.7% as 250K jobs added in October
The average workweek for all employees on private nonfarm payrolls increased by 0.1% to 34.5 hours in October. She felt she needed a high enough hourly wage to make up for the cost of child care for her three children.
An open frontier is seen as crucial to preserving the 1998 Good Friday peace accord that ended decades of Irish sectarian bloodshed.
The tough talk from Ireland came as shadow chancellor John McDonnell confirmed Labour would not support a temporary customs union with the EU.
Hopes that a deal could be struck as early as next week have faded because of the continuing clash between London and Brussels over the future status of the Irish border.
Meanwhile, a Survation poll of 20,000 people for Channel 4 estimated Remain would win another in/out referendum by 54%-46%.
In regards to customs checks, the deal is said to include an agreement by the European Union that checks on goods can take place at places of manufacture, or in shops, instead of at the border.
But London and the bloc have still not agreed how long such an insurance policy would last. Insisting that negotiations are "ongoing" at a technical level, the Commission's chief spokesman summed up progress by telling reporters: "Not there yet".