The prime minister repeatedly refused to confirm that he will announce the scrapping of the Birmingham to Manchester leg of the project in his keynote speech to the Tory conference on Wednesday.
The row has dominated the annual get-together, which is taking place in Manchester.
Andy Street, the Conservative mayor of the West Midlands, told an impromptu press conference last night that the PM would be “turning his back on a once in a generation opportunity to level up” if he axes the Manchester line.
On BBC Breakfast this morning presenter John Kay told Sunak: “When you took last year you told us ‘the end of chaos’, you were going to be in control, it was all going to be calm and managed properly.
“But a lot of your MPs feel you have lost control over HS2, that you might want to talk about crime and justice today, but all anybody at the conference is talking about is the fact that you haven’t announced a decision on HS2.
“They would say that this is a distraction, even a mess, of your own making.”
The PM replied: “I can tell you, because I’m at the conference, that that’s not what they’re talking about.
“What they’re talking about is our net zero ... an example of me making a long-term decision for the country, even when it’s not easy.”
Asked on Times Radio if he would announce his decision tomorrow, Sunak again dodged the question.
He said: “Without getting into the nitty gritty of all the speculation, I am always going to take the time to get things right for the country.”
On ITV’s Good Morning Britain programme, presenter Susanna Reid told the prime minister: “They’re straight talkers up here in Manchester, they want a straight answer.”
But Sunak said: “What they’ll see from me is that I’ll take the time to get the decision right for the country.”