The Secretary of State should call a snap Assembly election if Stormont power-sharing is not restored by October, his Labour opposition counterpart has said.
Peter Kyle, Shadow Secretary of State for Northern Ireland, said legislation requiring a poll "has to be followed" if no new Executive is formed by the October 28 deadline.
But he said it would be a "sign of real failure" if the public are asked to vote again this winter just months after the last Stormont election.
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In an interview with Belfast Live ahead of Labour's annual party conference, Mr Kyle also slammed the Conservative government's "petty" handling of Brexit's Northern Ireland Protocol impasse.
He said the Good Friday Agreement would never have been signed if the current Tory administration had been in power at the time.
The MP added: "The previous generation with the Labour government could deliver the sensitivity, the framework that delivered peace in Northern Ireland. This lot are falling out because they can't even negotiate a prawn sandwich across the Irish Sea."
Stormont's power-sharing institutions have been in limbo for months with the DUP blocking their restoration in protest over the protocol trading arrangements.
If there is still no new Executive formed by October 28, Secretary of State Chris Heaton-Harris is required under current laws to call a snap election within 12 weeks.
Mr Heaton-Harris has insisted the prospect of him calling a winter election is not an "idle threat", saying that he has "no intention of changing the legislation".
Mr Kyle said "the legislation has to be followed", but added: "I think it would be a sign of real failure if we have to return to voters in Northern Ireland having not sat a single day, meaningfully, of the democratic institutions since the last election."
The MP did not rule out supporting any eleventh-hour move by the government to delay a snap election, saying he would "take as many soundings as I can" from the Stormont parties and across Northern Ireland.
"Now, that being said, I do believe that if we pass legislation in this place, we should stick to it as much as possible. That's my instinct," he added.
"We shouldn't change the rules of an election on the eve of election. I don't think that's desirable."
Mr Kyle described the government's Westminster bill aimed at overriding the protocol as "incredibly provocative" and "destabilising for the island of Ireland".
He "cannot see the circumstances" where the Protocol Bill will pass through Parliament by the end of October and he would be "quite surprised" if it was passed by Christmas.
The shadow Northern Ireland secretary said that while he and Labour voted against the protocol, they "respect the rule of law" and negotiation with the European Union is the "only one way forward".
Calling for fresh engagement between London and Brussels, he hit out at the government not participating in meaningful talks "since March".
"Are we honestly saying that two territories like Britain, United Kingdom and the European Union, cannot get around the table and sort out the agreement where one wants to call it a 'fast track' and another wants to call it a 'green lane'? That's how petty this has become," he said.
On the cost-of-living crisis, Mr Kyle criticised as "half-baked" the government's plan to give a payment of £100 to home heating oil customers, who make up two-thirds of households in Northern Ireland.
He said: "This is an afterthought, and it's paled into insignificance compared to what the government is going to be spending on households across the rest of the United Kingdom.
"So this strikes me as being half-baked, not fit for purpose and not matching the scale of the challenge."
Mr Kyle was among those who met King Charles III at Hillsborough Castle last week in his first trip as monarch to Northern Ireland following the death of his mother, Queen Elizabeth II.
He said the way Sinn Fein vice-president Michelle O'Neill and Assembly Speaker Alex Maskey presented themselves during the visit was "really respectful" and "very much appreciated across the political spectrum in London".
He said Mr Maskey's speech expressing condolences on behalf of the people of Northern Ireland was "very well-judged" and "you could certainly see flashes of emotion going across King Charles' face".
Some unionists such as former DUP leader Arlene Foster and TUV leader Jim Allister criticised media focus on Sinn Féin's role in tributes to the late Queen and welcoming the new King.
Mr Kyle said politicians should not be surprised that parties will "use situations in order to show their best face" and this is "all part of the trade of politics".
"But I will say this, in slightly sharper tones, that the DUP and the unionist movement has a lot more agency than perhaps it let on to at times like this," he added.
"The reason that you had a Sinn Fein representative doing those speeches was because there's no functioning democratic institutions.
"So it's not as if the DUP or anybody that may or may not have had criticisms of the presentation or the profile of Sinn Fein In that period, it's not as if those people didn't have agency in the either the outcome or the presentation."
Mr Kyle has been Shadow Secretary of State since last November, during which he has seen three Northern Ireland secretaries come and go.
Earlier this month Mr Heaton-Harris succeeded Shailesh Vara, who had been Secretary of State for just 61 days after Brandon Lewis resigned in the turmoil that ended Boris Johnson's premiership.
Mr Kyle said he was giving Mr Heaton-Harris the "benefit of the doubt" at this stage, but he "wasn't sorry to see the back of Brandon Lewis".
He said the divisive Troubles legacy bill, which proposes an amnesty for perpetrators of Troubles-related crimes in exchange for co-operation with a new information retrieval body, was "peak Brandon".
He added: "It was crass, it was in insensitive, and it was wholly focused on the needs of the Tory party at the expense of some extremely vulnerable people in Northern Ireland who are experiencing extreme pain from the grief and trauma that they and their families have been through, and that for me was simply unforgivable."
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