Boris Johnson is expected to confirm HS2 will go ahead on Tuesday, causing splits in the Conservative Party over cost and environmental concerns.
The controversial high-speed railway scheme is likely to be discussed at a Cabinet meeting in the morning, before the Prime Minister makes a statement on the project.
It has been reported that Mr Johnson will give the green light for Phase 1 between London and Birmingham, but will say more analysis is needed on the cost of the route extending further north to Manchester and Leeds.
High-speed trains will also run beyond the new lines on existing tracks as far as Edinburgh and Glasgow.
Conservative MPs in seats along the route south of Birmingham are among those who are angry over HS2’s cost and impact on the environment.
HS2 critic and Lichfield MP Michael Fabricant described the expected announcement as “very disappointing” and warned HS2 will cause “immense” damage to the countryside.
The Tory benches erupted into shouts of “No” when Mr Johnson was asked if he agreed that HS2 should go ahead during Prime Minister’s Questions last month.
Mr Johnson’s most senior adviser, Dominic Cummings, is said to be in favour of scrapping the scheme.
HS2 Ltd – the Government-owned company responsible for developing and building the railway – says it will boost capacity and cut journey times.
Former HS2 Ltd chairman Douglas Oakervee was commissioned by the Government in August 2019 to lead a review into whether or not the programme should be scrapped amid rising costs and delays.
It has been widely leaked that the review found HS2 could cost up to £106 billion, but concluded that “on balance” it should continue.
HS2’s original budget was £32.7 billion at 2011 prices.
It was due to open in December 2026, but HS2 Ltd chairman Allan Cook said last year it would be “prudent to plan for an opening between 2028 and 2031”.
Last month, Whitehall’s spending watchdog said the scheme is over budget and behind schedule because its complexity and risks were under-estimated.
The National Audit Office warned that it is impossible to “estimate with certainty” what the final cost could be.
HS2 has been the subject of years of intensive lobbying from politicians and opposition groups.
Several environmental organisations claim building it will cause huge damage to natural habitats, including dozens of ancient woodlands.
Communities living on or near the route have expressed anger at the impact on their lives, while many people have said the project is simply too expensive and the money would be better spent elsewhere.
Labour’s shadow transport secretary Andy McDonald claimed HS2 has been “appallingly mismanaged” by the Conservatives Party.
He called for the high-speed railway to be integrated with Crossrail for the North – a proposed boost for rail services between Liverpool and Hull – and eventually extend high-speed lines to Scotland to “remove the need for domestic flights”.
Neil Lancefield is PA Transport Correspondent.