Irish Prime Minister Leo Varadkar said that he held a phone conversation with German Chancellor Angela Merkel on Thursday morning during which both leaders agreed that no reassurances or guarantees sought by the British side should contradict what has been agreed in the Withdrawal Agreement.
Liberal Democrat leader Sir Vince Cable called on the government to protect security in Northern Ireland by ending the "brinksmanship" over a no-deal exit from the EU.
On the matter of the Good Friday Agreement, the unionist politician noted that "The Irish government has been preparing for a No Deal scenario and in its document... they haven't mentioned anything about what they would do along the border, what hard infrastructure they would put along the border".
"The responsibility for this lies primarily with the European Union", he said.
The Democratic Unionist Party (DUP) who are now propping up Theresa May's Tory government still remain adamant that they will not concede to an Irish backstop on the border between Northern Ireland and the Republic.
"EU spokespersons have gone out of their way to reiterate that there will be no renegotiation of the Withdrawal Agreement".
"The threat of no deal can be taken off the table at any time by the United Kingdom parliament either by ratifying the agreement that the 28 governments have made or by seeking the extension to Article 50 to allow more time for us to negotiate what needs to be negotiated".
As many as 1,000 extra police officers from Britain have been requested by the Police Service of Northern Ireland, according to reports from The Guardian.
The prime minister also defended herself against critics by asking them to provide an alternative to the plan she had negotiated.
The UK Government has said it does not want a hard border reimposed on the island of Ireland.
In comments that underline the difficulty Mrs May faces in getting her deal through the Commons this month, Sammy Wilson said there was "not any way" in which the DUP could support the Prime Minister's deal.
"Brussels must now demonstrate that if it truly cares about Northern Ireland, then erecting a new east-west barrier should be no more palatable than having any new north-south barriers", he said.
After the first new year meeting of Ireland's Cabinet, Varadkar said that ministers had chose to prepare Brexit legislation in detail over the next two weeks, but that any no-deal legislation would not be introduced to the Dáil until March.