After receiving a red rating, HS2 has been officially declared ‘unachievable.

The government’s infrastructure watchdog has deemed the HS2 project “unachievable”, due to its severe delays and soaring cost.

After analyzing plans for construction of the two first phases of the high speed line from London to Birmingham and Crewe, Infrastructure and Projects Authority stated that the project, as it stands, is not deliverable.

Campaigners will use the findings of the IPA, which is at the core of the government and reports to both the Cabinet Office, and the Treasury.

The scheme was opposed by many wildlife groups as well as residents of the affected areas. The construction of this scheme has destroyed vast swathes in the countryside.

The plans for construction of the two first phases were given a “red” rating. The IPA’s annual report on large projects stated that the “successful completion of the project seems to be impossible”.

The report added that “major issues exist with the project definition, schedule and budget, as well as quality or benefits delivery. These problems do not seem to be resolvable at this time.” It may be necessary to rescope the project and/or reassess its viability.

Tony Berkeley, a Labour MP who has been an outspoken critic of HS2 said on Sunday that the scheme should be scrapped immediately. The Treasury has its own report that says the scheme will not be achieved. “What more proof do they require?”

He said: “Everyone is aware that the money would be better spent improving the existing rail infrastructure, particularly Northern Rail. Someone needs to make the decision.”

Christian Wolmar is a transport journalist and broadcaster. He said that the most alarming aspect of the report, was the suggestion that the government has no idea how it can resolve the problems with the scheme.

Joe Rukin, founder of the Stop HS2 Campaign Group, described the project from the start as “an unmitigated catastrophe”.

He said, “It’s a massively damaging project for the environment, prohibitively costly, unwanted, unloved, and unneeded” before the IPA Report was released. It only exists due to the hard lobbying of the construction industry who wanted the most expensive rail in history.

HS2 had been scheduled to open by 2026, but now is projected to open from 2029 to 2033 due to construction problems and rising costs. The budget for the entire project was £55.7bn in 2015. However, the cost target, excluding the eastern section from the West Midlands into the East Midlands, is now between £53bn to £61bn, at 2019 prices.

Mark Harper, the transport secretary, announced in march that work on Euston will be paused for a period of two years, as costs have ballooned from £2.6bn to 34.8bn.

Mark Thurston , HS2’s chief executive , announced his resignation this month after six-and-a-half years as the company’s leader. This announcement was made as the construction of phase 1 between London and Birmingham reached its peak. More than 350 sites were involved in this work.

Department for Transport is under pressure to make cost-savings on this project due to the rising cost of raw materials.

DfT spokesperson: “Spades have already been in the ground for HS2, with over £20bn of investment to date, and supporting more than 28,500 jobs. We are committed to delivering the HS2 project in a cost-effective manner for taxpayers.

“HS2 will transform the future for generations, improving connectivity and growing the economy.”