Speaking to ITV News, the prime minister said "no decision" had been made about the future of the high speed rail link, and repeatedly side-stepped questions over whether the Northern Leg would still go ahead.
Those close to the prime minister and in the Treasury have been keen to push the economic case for scaling back the project and are hesitant to potentially throw good money after bad.
Cabinet ministers - from Chancellor Jeremy Hunt to Defence Secretary Grant Shapps - have publicly argued that high inflation, sparked by the Ukraine conflict and the coronavirus pandemic, have put pressure on government finances and made the current iteration of HS2 unsustainable.
Earlier this week, the Times newspaper revealed that Mr Sunak was personally "alarmed" by the soaring costs.
The project, which was estimated to cost £55.7 billion in 2015, could cost upwards of £100 billion, according to estimates leaked in 2020.
But the ramifications of scaling back a flagship policy ahead of a general election would be stark - and, in the eyes of some conservatives, could outweigh any potential financial savings.
HS2 was central to the government's promise to level up the UK and is a policy that cuts directly into the heart of the Midlands and North of England, and in some Tory red wall seats - hard won from Labour in the last general election.
Many conservative MPs I have spoken to in the region have privately voiced concern over the message being sent to voters, and argue public infighting over the issue is a distraction from the party's broader message.
Certainly, instead of outlining the government's core priorities and policy objectives, the prime minister was forced to spend the morning rejecting claims that he's not committed to levelling up.
Ministers I have spoken to say discussions are ongoing and that a final decision on the Northern Leg of the project has not yet been made.
But having let speculation and rumours run rife, the government is now in danger of losing the narrative on this issue.
If ministers opt to scrap or delay the Northern leg, it could look tone deaf given the scale of opposition from regional mayors who have now accused the government of treating Northern like "second class citizens".
Were the government to maintain the project as planned, it could give the impression that it caved to pressure from vocal Tories, including former prime ministers Boris Johnson and David Cameron and former chancellor George Osbourne.
Without a quick answer on the issue, the future of HS2 is guaranteed to continue to dominate newspaper headlines and TV bulletins, and will undoubtedly overshadow the party's conference due to be held in Manchester this weekend.
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