Construction has officially begun on High Speed 2 (HS2), a new rail network designed to connect London to the north of England.
Prime minister, Boris Johnson, said the service would “fire up economic growth and help to rebalance opportunity”.
He endorsed the rail link in February, with formal government approval granted in April despite lockdown.
HS2 is set to link London, Birmingham, Manchester and Leeds.
It is hoped the 20-year project will reduce passenger overcrowding and help rebalance the economy through investment in transport links outside London.
Critics have, however, branded the rail network a white elephant and argued it will cost jobs.
Johnson said: “HS2 is at the heart of our plans to build back better – and with construction now formally underway, it’s set to create around 22,000 new jobs.
“As the spine of our country’s transport network, the project will be vital in boosting connectivity between our towns and cities.
“But HS2’s transformational potential goes even further.
“By creating hundreds of apprenticeships and thousands of skilled jobs, HS2 will fire up economic growth and help to rebalance opportunity across this country for years to come.”
When the project was mooted in 2009, it was expected to cost an estimated £37 billion and when the official price tag was set out in the 2015 Budget it came in at just under £56 billion.
But an official government report has since warned that it could cost more than £100 billion and be up to five years behind schedule.
Transport secretary, Grant Shapps, said: “Today marks a major milestone in this government’s ambitions to build back better from Covid-19.
“Shovels in the ground to deliver this new railway means thousands of jobs building the future of our country’s infrastructure.
“This fantastic moment is what leaders across the North and Midlands have called for – action to level up our country by boosting capacity on our railways, improving connections between our regions, and spreading prosperity.”
Some critics of HS2 describe it as a “vanity project” and say the money would be better spent on better connections between different parts of northern England.
Others, such as the Stop HS2 pressure group, say it will cause considerable environmental damage.
Mark Thurston, chief executive of HS2, said: “This is a hugely exciting moment in the progress of HS2.
“After ten years of development and preparatory work, today we can formally announce the start of full construction, unlocking thousands of jobs and supply chain opportunities across the project.
“We are already seeing the benefits that building HS2 is bringing to the UK economy in the short term, but it’s important to emphasise how transformative the railway will be for our country when operational.
“With the start of construction, the reality of high-speed journeys joining up Britain’s biggest cities in the north and Midlands and using that connectivity to help level up the country has just moved a step closer.”
An estimated 400,000 supply chain contract opportunities for UK businesses will be created during phase one of HS2, supporting thousands of jobs on site and many more around the country.
It is estimated that around 95 per cent of those contract opportunities will be won by UK-based businesses and around two thirds of those will be small and medium sized businesses.