BORIS Johnson and Sadiq Khan have come under fire after saying that London’s new Elizabeth rail line will be a “big moment” for the entire country.

The Prime Minister and London Mayor both suggested the new line would benefit the four nations of the UK.

The train line is estimated to have cost £18.9 billion after a three and a half year delay, around £5bn over budget.

Johnson and Khan both said the investment in London would benefit the whole UK economy - but many across the UK took issue with it being beneficial to them.

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The UK Prime Minister's Twitter account wrote: “As the Elizabeth Line opens to the public, we know it’s not just Londoners that will reap the rewards, but the whole country – because better transport grows the economy, levels up opportunity and creates jobs.”

While London Mayor tweeted: “Today’s the day: The Elizabeth line opens! This is a big moment for London and the entire country. Get ready for modern trains, step-free stations and reduced journey times across the capital and the South East.”

Responding to the comments, SNP MP Emma Roddick told The National that many of her Scottish constituents will never have to use London's trains.

She said: “Highlands and Islands residents are used to hearing that a project we’re never going to see is somehow good for us, often as a justification for skyrocketing spending well over budgets and estimates.

“We’ve been here before: hundreds of millions spent on behalf of Scotland for high-speed trains that may never reach this country.

The National: Passengers on board an Elizabeth Line train in London, as the new line opens to passengers for the first time. The delayed and overbudget line will boost capacity and cut journey times for east-west travel across LondonPassengers on board an Elizabeth Line train in London, as the new line opens to passengers for the first time. The delayed and overbudget line will boost capacity and cut journey times for east-west travel across London

“While I’m aware London feels like the entire world to some politicians down south, the fact is that there is life beyond their city.

“Many of my constituents will never have cause to see the London Underground.

“A big moment for my region will be when we have real, proportional representation for the Highlands and Islands in a Scottish Parliament with full powers of its own.”

Gavin Newlands MP, the SNP's transport spokesperson at Westminster, agreed. While he supported investment in public transport anywhere, he suggested the south east of England had been getting more than its fair share.

He told The National: "Investment in public transport, wherever it is, has to be welcomed but the plain fact is London swallows a massively disproportionate slice of the spending pie and has done so for decades.

“Instead of levelling up, the Tories seem intent on powering up the South East at the expense of everyone else as usual. 

“In Scotland we have a Scottish Government that is directing transport investment across the country, whether that’s the new Levenmouth rail line, upgrading the Aberdeen – Inverness line, modernising’s Glasgow’s Subway, or rolling out the biggest investment in active travel in history. But the regions of England don’t have real devolution and are forced to fight for scraps from the UK Government’s table.

“The UK Government doesn’t work for most of the UK – its focus is Greater London and the South East of England, while the rest of England is left on the sidelines; one look at recent announcements on the cancellation of the Eastern leg of HS2 and the scaling back of upgrades to the north of England’s rail network shows the Government’s priorities.”

Speaking after the line opened, Johnson said: “As the Elizabeth line opens to the public, we know it’s not just Londoners that will reap the rewards, but the whole country – because better transport grows the economy, levels up opportunity and creates jobs.”

The Government said the Elizabeth line project is supporting 55,000 jobs, 1,000 apprenticeships and is forecast to boost the economy by £42 billion.

The mayor of London, Sadiq Khan, echoed the PM’s sentiments, saying the line’s opening would “provide a crucial economic boost to the whole country”.

But across the UK, anger erupted over the comments, particularly in Wales and the north of England.

Plaid Cymru councillor Jac Jones tweeted: “It takes 9 hours to get from Bangor to Pwllheli by train, despite the two only being 25 miles apart. There is literally no benefit to this line for Wales.”

Another user replied to the Prime Minister’s post saying: “Invest properly in the North of England and beyond. HS2 in full (and extend HSR to Scotland and SW England) integrated transport plans for major cities and sort Leeds out with trams!”

While one person said: “Investment per capita in public transport woefully less in the midlands. But I guess we can sit back and watch the economy of London and the south east grow!”

Ken Borg also took issue with how the trainline will benefit his community, saying: "People in the southwest that live in the villages and towns that don't even have a train station or a working bus service will be ecstatic I'm sure.”

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Pete Badger added: “Good for London. But it's not a big moment for parts of the county where bus services are being cancelled, trains are sparse and chronic, and trams and underground don't exist.”

Yorkshire journalist Andrew Musgrove said the London line's opening came as cuts happened in other parts of England.

He said: “'The entire country'. Meanwhile, in the north east of England, bus services are being cut or cancelled, and prices are sky-high for bang average services. But hey, get the bunting out for the new Elizabeth line!”

Journalist Esther Beadle also took issue with Khan and Johnson's claims that the line will be a good thing for the whole country. She said: “Yes indeed, even I, sat in my flat in the east end of Newcastle can feel the reverberations of this momentous occasion … oh wait, sorry, nope.

"That’s just the rumbling echoes from the lack of decent regional rail in the north. Sorry, my bad!”