"I'll remain in this position by 2027," the Prime Minister stated, noting that if the interview was successful, he might welcome us into his official residence for a follow-up chat in the coming year.
There is never any break for those in the top job. Just an hour before the interview began, the PM had been speaking with Ukraine's Volodymyr Zelensky and working to work out exactly what had occurred in Venezuela, where his big political chum, US President Donald Trump, had recently attacked and captured its leader, Nicolás Maduro.
When the discussion, which was far more extended than typical, had concluded, Maduro had been charged in New York.
With the new year begins, Starmer seems to have had a degree of a refresh. Perhaps even just a bit of downtime with loved ones at Chequers, the prime minister's official country residence.
This appeared to have put him in better spirits than at the difficult tail end of 2025, a terrible year politically for him.
But are he and his allies deluding themselves if they reckon his political fate are poised to turn around?
The uncomfortable reality for the prime minister is that a significant number of his party members think he's underperforming at his job. A faction of them would rather take a risk and remove him in 2026.
However Starmer was dismissing such talk in the interview on Saturday morning.
Repeatedly he insisted he'd be "evaluated at the next election", arguing no one would remove his term from him – even if the best chance of preventing Nigel Farage and Reform UK reaching No 10 could be for Labour to replace its leader.
"We are in the battle of our generation and I intend to be at the forefront," he said.
The issue for the prime minister is that he will be judged long before then – in a major set of elections in May throughout the UK. He sought to argue, perhaps excessively, that they are concerning who runs local authorities, and who runs the governments in Holyrood or Cardiff – and unrelated to Westminster.
Accurate – up to a point. But although he may not want to admit it, No 10 will be judged by those elections too.
This did not stop Sir Keir suggesting that there were no circumstances under which he would step down, even if a his MPs contested his leadership for the job, should those elections prove very poor for Labour.
He attempted to account for his low poll ratings by saying the public was naturally eager for things to get better. He tried to convince me, and the nation, that this year would be different.
The economic situation would improve despite rising unemployment, he claimed, when policies the government implemented during their first choppy year began to take effect.
His big message is that in 2026 the country will "turn the corner".
The prime minister may have spoken with more energy than observed from him for a some time – more relaxed, perhaps, with a longer slot to talk.
But despite facing calls from within his own party for a more decisive strategy, with greater political direction, more vigour, more pace and more urgency, his arguments were repeated ones.
Given that he is in such significant political trouble, does he need a new narrative?
No administration, and certainly not one that has been unpopular for an extended period, has everything its as planned.
The Prime Minister's problems are not only because governing is hard, but because he and his team have erred, even in the recent past.
The PM expressed regret that he was sorry for saying he was "delighted" to welcome back the Egyptian-British activist Alaa Abd El Fattah to the UK after an backlash when comments he'd previously made – including calls for Zionists and police to be killed – surfaced.
Starmer attributed it to "the system" for not realising what the activist had said before – a more diplomatic way of saying it wasn't his responsibility.
And he is facing obvious political risks as the year progresses. His close relationship with the US president entails a new jeopardy after Trump's intervention on Venezuela.
Having interviewed Sir Keir Starmer, a former human rights lawyer who opposed the war in Iraq, over a long period, the idea he would be content with these events seems far-fetched.
He told me he was a "lifelong champion of international law" but we "just do not have the full picture at the moment".
Critics wanted him to criticise the action before the interview. And the government is expected to face increased demands to give an clear view in Parliament in the next few days.
There has also long been growing desire in the Labour party to reverse or renegotiate some of the results of Brexit.
Sir Keir disputes he's doing that, but his new firmer plan to move closer with the European trading bloc – the giant economic European market – will likely elicit howls that he is reneging on his pledge never to try to reverse the results that stemmed from Brexit.
A commitment to cosy up to more of the single market will please some on his side of the party, but it is simple material for Reform and the Conservatives to