IRELAND'S top diplomat in Scotland has warned that the threat of a hard Irish border has not disappeared.

Mark Hanniffy, the Consul General of Ireland in Scotland, said a failure to avoid a border posed a danger for Anglo-Irish trade relations.

The intervention came as EU officials reportedly savaged Theresa May's proposals for the future of the Irish border after Brexit.

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Downing Street insists there would no return of a hard border with Ireland after Brexit, and said it did not recognise reports that Brussels had attacked its proposals.

However, Hanniffy, a former top level Irish foreign affairs and trade official, said there was “still quite a bit of work” needed to secure a deal over border access.

The Edinburgh-based diplomat highlighted his concerns in an exclusive interview with the Sunday Herald.

Hanniffy said a deal between the EU and the governments in Dublin and London to maintain the free flow of goods, without border checks was still some way off.

He said: “There's still quite a bit of work to do in the context of negotiations that are underway.

"We're not yet at the stage where we're negotiating an agreement."

Hanniffy said a physical border infrastructure on the island of Ireland would have a harmful impact on the Irish-UK trade relationship.

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The former senior official at Ireland's department of foreign affairs and trade in Dublin said: "It depends on the nature of the future EU-UK relationship.

"The UK remains one of Ireland’s largest economic partners.

"Undoubtedly if there are any type of barriers to trade it will have an impact on business and trade across these islands."

Hanniffy previously served as an Irish representative at the United Nations in Geneva.

However, he said that the UK and EU member Ireland had to come up with “new ways” to deliver the Good Friday Agreement after Brexit.

He said that it was inevitable due to Northern Ireland leaving the EU while the Irish republic remains a member.

Hanniffy said: "In the last week or so we've been celebrating the 20th anniversary of the Good Friday Agreement signed back in 1998.

"That agreement was essentially negotiated against the backdrop of a supportive framework based on a shared arrangement between EU members.

"A lot of the elements which have been put in place essentially rely at the moment on our shared European membership.

"In a situation where one part of Ireland is in the EU and another is outside the European Union it does cause some challenges and complexities.

"The way in which we have been implementing the Good Friday agreement for the past 20 years has reflected a shared European Union framework.

"We need to come up with slightly new ways because of the fact that we are not going to be able to do it in a European framework.

"That will inevitably give rise to challenges."

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Hanniffy's remarks came as the UK Government's plans to resolve the matter faced sustained criticism from the EU at a meeting last week.

The UK wants to use technology to help goods flow freely and avoid regulatory alignment between the north and south.

However, senior Brussels diplomatic sources reportedly said that the UK Prime Minister's plan for avoiding a hard border in Northern Ireland was subjected to a “systematic and forensic annihilation” at a meeting between senior EU officials and Olly Robbins, the UK’s lead Brexit negotiator.

The EU wants to present an agreed solution on the issue to a summit meeting of European leaders in June.