The former chief Brexit negotiator has warned that the EU will not back down in the dispute over the Northern Ireland Protocol.
Speaking in Dublin, Michel Barnier said: " The EU must not and will not back down and the protocol of Ireland and Northern Ireland must and has to be respected by the British Government."
The DUP withdrew from the Executive in protest against the post-Brexit trading arrangements.
Mr Barnier's comments come after a warning from the Secretary of State that a Stormont election will be called if an executive is not functioning within the next month.
This could potentially have the public casting their vote as early as December 16. The Secretary of State push this back into the new year.
Northern Ireland’s Foreign Affairs Minister Simon Coveney was optimistic that a solution can be found despite the increasing international challenges.
He said that work would be done to try and have a functioning Northern Ireland executive before the October 28 deadline for an election to be called.
“I believe that we can move the protocol issues along significantly over the next month on some of the core issues that matter, and I believe that can and should be enough to justify the setting up of an Executive again.
"The only way we can remove checks on certain products is if we know those products are staying in Northern Ireland and are not at risk to the rest of the single market and I think we can do a lot in that space actually."
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