DUP: 'Threat of violence' to Sir Jeffrey Donaldson has been reported to the PSNI

In a statement the party said: “The details have been reported to the PSNI and we trust those responsible will be held accountable for their actions. There is no place for the threat of violence in democratic politics”.

A PSNI spokesperson said: “We do not discuss the security of individuals and no inference should be drawn from this".

Sir Jeffrey told MPs yesterday: “I’m proud of the service that I have given, unlike some others, to my country when I put on the uniform of the Ulster Defence Regiment to protect everyone in the community from terrorism and violence.

“And yet today, because of the stirring up that is going on, I was threatened, threatened by those who never put on a uniform, by those who haven’t served our country.”

He added: “They are threatening people like me, who’s working day and night to try and find solutions and to move Northern Ireland forward on a basis that the vast majority of people can support.

“Well I would just say this to those who stir up, and those who threaten: the provisional IRA attacked me in the past and it didn’t deflect me from the task that I have, and my colleagues have, to do our job and to get the best that we can for Northern Ireland.”

The developments come amid increasing tensions within unionism over the parameters of any deal on the Irish Sea border and the restoration of Stormont.

Orange Order Grand Secretary Mervyn Gibson said Sir Jeffrey's deal must be right - and the green lane must go. However he said that didn’t necessarily mean that the EU needed to change regulations or legislation – and could involve Brussels being kept across changes such as renaming certain parts of the arrangements.

However the TUV and anti-protocol activist Jamie Bryson have rejected such an approach and demanded the removal of key pieces of EU and British legislation which underpin the Windsor Framework.

Sir Jeffrey was set to consult with unionist and loyalist groups this week – but has been scathing about what he says is the failure of his unionist opponents to deliver changes to the NI Protocol.