Mark Reynolds, chief executive of the Mace Group, said that the government’s plan to end the line at Old Oak Common – in west London – means it would take commuters longer to travel the roughly five further miles to central London than the previous 114 miles from Birmingham.
“It will take longer to get from Old Oak Common to get into London than it would to come from Birmingham,” Mr Reynolds said, emphasising the suggestions of stopping short of Euston, was a big mistake and “came out of nowhere”.
The government has ordered work on the site to be paused, with the firm already demobilising 1,200 workers and construction hoardings left unattended.
Now ministers are threatening to ditch the Euston rebuild altogether and end HS2 at Old Oak Common.
Passengers would have to switch to other existing services for the final five miles to central London. The government is also considering dropping plans to take the line to Manchester.
Mr Reynolds, whose firm was tasked with redeveloping Euston and other new stations for HS2, said the Government’s decision to scrap large chunks of the project “came from nowhere”.
He also warned that his firm would now be more cautious about taking on major projects in the UK as a result of the indecision.
“One minute the prime minister and chancellor were standing up telling everyone the rail link is going to Euston, and three weeks later they said it is being paused for two years,” he told BBC Radio 4.
“The hoardings at Euston will remain as a scar on that part of London,” said Mr Reynolds.
It was vital to persuade ministers to go ahead with its original plan for HS2 because it would “benefit the whole country”, he said.
Mr Reynolds said it was “very rare that you work on a major scheme that gets stopped”, adding it “doesn’t normally happen in the UK, quite frankly at this scale”.
The government is yet to make an official announcement on the future of HS2. An update on the project was expected this week, but ministers are now thought to be reconsidering their cuts following a huge backlash.
But it is understood changes or delays to HS2 could still be announced in the autumn statement or spring budget.