A council chief executive has defended seeking advice from DUP MPs on a letter to the Cabinet Office voicing concerns over post-Brexit arrangements.

Mid and East Antrim Council chief executive Anne Donaghy was questioned by a Stormont committee over the letter she wrote to the Cabinet Office on January 30.

It included concerns over protests and alleged threats to staff at Larne Port, who were carrying out checks under the terms of the Northern Ireland Protocol.

The committee heard Ms Donaghy wrote that she was “aware of the involvement of paramilitary groups in recent protests at Larne Port”.

The staff involved were withdrawn over safety concerns on February 1.

Unionists and loyalists have opposed the protocol, saying it created a “border in the Irish Sea”, distancing Northern Ireland from the rest of the UK.

Ms Donaghy has been criticised by Sinn Fein, SDLP and Alliance MLAs for taking advice from DUP MPs on her letter.

She told the Agriculture Committee on Thursday that she sought advice from two MPs from the council area, East Antrim MP Sammy Wilson and North Antrim MP Ian Paisley, on who would be the most appropriate senior official to “engage with on these serious issues”.

Ms Donaghy said they directed her to their DUP colleague Sir Jeffrey Donaldson, who gave her a name to contact.

“It would be normal practice for Mid and East Antrim Council officials to engage regularly with our members of parliament on a wide range of issues that impact on the borough,” she said.

Ms Donaghy added it would be a “dereliction of my duty not to keep highlighting” governance issues around the ports, warning that the council fears a 10% increase in rates over implementing the protocol.

Mid and East Antrim mayor Peter Johnston also appeared before the committee, which is investigating the circumstances around withdrawal of port staff.

“I don’t think we can stick our head in the sand,” she told MLAs.

Mid and East Antrim mayor Peter Johnston also appeared at the committee, which is investigating the circumstances around withdrawal of port staff.

He told MLAs they did not expect to return to the committee “so soon” after appearing two weeks ago, “for a lengthy cross examination”.

He said he has been “exceptionally disappointed by the approach taken by this committee towards Mid and East Antrim Council and our chief executive”.

Mr Johnston outlined three concerns – the timeframe set for submission of responses and to appear before the committee as “unreasonable”, the focus “unfairly put on Mid and East Antrim Council and in particular our chief executive”, and an “inflammatory comment” calling for Ms Donaghy to resign.

“I think this is absolutely appalling considering this inquiry is still ongoing and the chief executive’s actions and integrity are without question,” he said.

Earlier a senior police officer stood by the assessment that loyalist paramilitaries were not behind alleged threats to port staff.

Threatening graffiti appeared in the area following the UK’s departure from the EU and there were also allegations that the number plates of staff vehicles were recorded amid negative social media commentary.

Police later said there was nothing to substantiate claims of loyalist paramilitary involvement and no evidence of “credible threats” to staff.

Last month Mr Johnston and Ms Donaghy told the Agriculture Committee they stood by the decision to withdraw staff on February 1, saying staff safety was their priority.

Assistant Chief Constable Mark McEwan said the intelligence assessment was that “loyalist paramilitaries were not behind the graffiti” and “were not intent in taking part in driving any of the action around portal activities”.

“That remains the case today,” he told MLAs.