In a speech in Belfast, shadow secretary of state for Northern Ireland Louise Haigh also cautioned against the dangers of a “damaging trade dispute” between the UK and the EU.
This week Brexit minister Lord Frost said triggering Article 16, which would effectively suspend elements of the protocol, would be the UK’s only option if differences with the EU could not be resolved.
The government has given the EU a December deadline to find a solution on the protocol, which was agreed as a way to maintain a free-flowing land border on the island of Ireland after Brexit.
The arrangement effectively keeps Northern Ireland inside the EU’s single market for goods, resulting in some checks for products crossing the Irish Sea from Great Britain, and is fiercely opposed by unionists.
Ms Haigh was speaking at the Senator George J Mitchell Institute for Global Peace, Security and Justice at Queen’s University.
She said: “If reports are to be believed, (Prime Minister) Boris Johnson is about to take another huge risk with stability.
“With tension rising in Northern Ireland and a cost of living crisis across the rest of the UK, the last thing that is needed is more poisonous instability and the prospect of a damaging trade dispute with our nearest trading partners.
“We’ve seen the damage this approach is doing. It is bringing the poison of division back to Northern Ireland. Corralling people to take sides.
“We know the dangers of that path. And that will never be the path to a sustainable solution.
“That’s why jobs, stability and livelihoods in Northern Ireland depend on the EU and UK finding a deal in the days and weeks ahead.”
Ms Haigh called on the UK and EU to bring Northern Ireland’s leaders and communities into the process to speak for themselves.
She said: “It is simply untenable for a government in Westminster, that few in Northern Ireland trust, to decide the future of communities who are excluded from the room.
“To say to the people of Northern Ireland – this is what we’ve decided: take it or leave it. Northern Ireland must be involved in these talks and in the huge decisions being made about their future.
“Remember what is at stake in the days ahead, remember what we have to lose and remember that a deal must first and foremost be secured in the interests of the people and communities of Northern Ireland.”
DUP chairman Lord Morrow has said Ms Haigh had failed to grasp how unsustainable the protocol really is.
“Labour has decided to join the EU in threats of ‘serious consequences’ if Article 16 is used,” he said.
“ Such speak is intemperate and ill-considered. It is most disappointing to see Louise Haigh come to Northern Ireland and engage in partisan and indeed naive political posturing. These issues are far too serious for such ill-judged, headline grabbing sound bites.
“Northern Ireland is losing £850m per year because of the protocol. Medicine companies are indicating they may not supply Northern Ireland. Not a single elected unionist in Northern Ireland supports the protocol. Rather than cement peace and stability, the protocol has perpetuated division and has been the source of instability. It is unsustainable.
“Whilst the Belfast Agreement enshrined the principle of consent, Northern Ireland has had its constitutional status undermined without even a single vote cast. As argued in court by the government, the Acts of Union have been undercut. The Labour Party who once stood by the Belfast Agreement, is now more concerned about singing from an EU hymn sheet and poking the prime minister than genuinely building a shared future with cross-community support.
“The Irish Sea border has cut Northern Ireland off from the rest of the United Kingdom. Trade has been diverted and there has been instability on the streets. The Frost/Sefcovic negotiations seem to be running out of road and Article 16 is a legitimate mechanism within the protocol to deal with such matters.
“The Labour solution seems to be to ignore unionists and sail full steam ahead with the protocol. Such an approach will lead to failure and have a serious impact on those of us who live here.”