Sir Jeffrey Donaldson and Micheál Martin to meet in Dublin

Democratic Unionist Party (DUP) leader Sir Jeffrey Donaldson is to meet Taoiseach (Irish prime minister) Micheál Martin in Dublin later on Friday.

It will be the first meeting between the two men since Sir Jeffrey took over as leader of his party.

He said the European Union should "change its tune".

The Northern Ireland Protocol was agreed by the UK and EU to avoid a hard border in Ireland.

It does that by keeping Northern Ireland in the EU's single market for goods.

That has created a new trade border in the Irish Sea, which is strongly opposed by unionists in Northern Ireland.

Speaking on BBC Radio Ulster's Good Morning Ulster programme, Sir Jeffrey said that "it is evident that the protocol is not working".

"[The UK government] recognises that the protocol is causing a lot of harm, not just in economic terms to Northern Ireland and to UK internal market, but is also harming the political process, and that is the message I will be taking to Micheál Martin," he said.

"The Irish government has a responsibility to recognise the harm that the protocol is doing to political, economic and social stability in Northern Ireland and it has a responsibility to act on that as a member state in the EU but also as a party to the Belfast and other agreements.

"Right now our relationship with the rest of the United Kingdom is being seriously harmed by the protocol and, in those circumstances, that has consequences for our relationship with Dublin.

"If the relationship east-west between Great Britain and Northern Ireland is being harmed by the protocol we cannot sustain a position where it's business as usual on a north-south basis and nor will we."

The DUP leader said Northern Ireland had been left in "an untenable position", adding that he will "be making that clear" during the meeting.

He also said that it is his understanding that some aid workers from Northern Ireland, who work for an Irish aid agency, have not yet been evacuated from Afghanistan.

He said he plans to raise the issue with Mr Martin on Friday.

Earlier, Sir Jeffrey said the DUP continued to make its case about the protocol in London, but that Dublin "also has a key role to play".

He said: "It was the then Taoiseach Leo Varadkar who insisted on such arrangements with his fellow EU leaders.

"I will be asking the taoiseach to recognise the flaws of the protocol and join with us in arguing in the corridors of power for change.

"It is time for Brussels to change its tune. It either changes course or it will have to take responsibility for Northern Ireland drifting backwards."

Mr Macron has, in the past, ruled out any renegotiation of the protocol.

During his visit to Áras an Uachtaráin, the Irish president's residence, Mr Macron wrote in the guestbook that Ireland "occupies a precious place in the heart of the European dream".

Mr Macron's note explained that France would remain a "faithful friend for the future".

Less than three months since then-DUP leader Edwin Poots went to Dublin for talks with Micheál Martin, now it's his successor's turn.

Don't expect much in the way of different messaging, though.

The warnings over DUP attendance at north-south meetings on the protocol are likely to be repeated by Sir Jeffrey.

He wants Dublin and, by extension, Brussels, to change course on the protocol - a request the taoiseach has heard before and repeatedly rejected.

This summer has seen politicking over the protocol largely parked, due to the pandemic and other pressing issues.

But today's meeting is a reminder that further clashes are coming.

Mr Poots said Mr Martin recognised the "genuine concerns in unionist and loyalist communities around the protocol".

But Mr Poots was ousted within 50 days of becoming DUP leader and was replaced by Sir Jeffrey.