The government only has until Tuesday this week to tell MPs about a large change to plans for the railway line, before the Commons then breaks for the conference recess until 16 October.

Labour is also being cautious with the multi-billion pound railway, with shadow chancellor for the Duchy of Lancaster Pat McFadden telling the BBC that "we want to see the railway being built, but we've also - like everything else - got to look at the cost of everything we do".

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In March this year, the government announced a two-year delay to the section of the project between Birmingham and Manchester, with services not expected to begin running on that part of the line until the 2040s.

Some estimates put the total cost of HS2 at over £100bn, and the project was rated "unachievable" by the infrastructure watchdog.

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Foreign Secretary James Cleverly is the most senior minister to be asked about recent reports the branch to Manchester may now be completely axed.

He told Sunday Morning With Trevor Phillips: "It's an important piece of infrastructure, the prime minister is absolutely committed to levelling up. This is part of that levelling up."

Asked if this meant the line would run to Manchester, the foreign secretary said: "We've always got to make sure that the sequencing is right.

"What leaders in devolved government want, what investors in the UK want, is predictability - and therefore we will make sure they know exactly what is going on."

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This mirrors a similar lack of commitment and clarity to the Manchester branch this month - from both the Home Office minister Chris Philp, and the prime minister's spokesman.

Concerns about whether the route would reach Manchester at all arose after The Independent published images showing what appeared to be government briefing documents.

These outlined how the government has already spent £2.3bn on stage two of the railway from Birmingham to Manchester, but that up to £35bn could be saved by abandoning the phase.

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Financial decisions are currently being made by the chancellor, Treasury and government as a whole in the run-up to the autumn financial statement in November.

Mr McFadden's refusal to commit to the branch gives Labour room to manoeuvre if the line to Manchester is cut - as reinstating the commitment would add tens of billions of pounds to the party's spending plans.