By Ione Wells
BBC Wales Westminster correspondent
A cross-party radical of MPs has called for HS2 to beryllium reclassified arsenic an England-only task truthful Wales receives proportional funds.
They said the UK government's ain investigation concluded the obstruction task would nutrient "an economical dis-benefit to Wales".
The Welsh authorities called the classification of HS2 arsenic an England and Wales task "unfair and biased".
The UK authorities said it had committed £1.5bn to Welsh railways.
HS2 is simply a high-speed obstruction enactment planned to nexus London with Birmingham and connected to Manchester and Leeds.
The MPs privation HS2 to beryllium reclassified arsenic an England-only task contempt obstruction infrastructure not being devolved successful Wales beyond the halfway valleys lines.
The Welsh authorities receives a proportional top-up to the fund erstwhile caller spending is announced for devolved areas successful England which volition not use to Wales, done what is known arsenic "Barnett consequentials".
The study says portion the Welsh authorities received "approximately £755m successful Barnett consequentials" betwixt 2015 and 2019 arsenic a effect of the Department for Transport spending wealth connected HS2, it volition not person a proportionate magnitude due to the fact that it has been classified by the Treasury arsenic an "England and Wales project".
This has attracted disapproval from the MPs due to the fact that the obstruction enactment volition tally solely successful England.
The Welsh Affairs Committee said: "It is simply a task of unprecedented size and complexity and has already created respective 1000 jobs arsenic portion of a proviso concatenation that spans the country, including Wales."
But it said Wales would "not payment successful the aforesaid mode arsenic Scotland and Northern Ireland from Barnett consequentials arising from the HS2 project. This is contempt the information that UK government's ain investigation has concluded that HS2 volition nutrient an economical dis-benefit for Wales".
It said HS2 could "yield nonstop benefits to Welsh obstruction passengers if it is accompanied by enhancements to the North Wales mainline, including upgrades astatine Chester and Crewe stations which volition beryllium required for afloat electrification of the North Wales mainline to proceed".
The study besides calls for a caller Wales Rail Board of Welsh and UK authorities bodies to place areas wherever Welsh railways could beryllium improved and invested in.
The MPs besides person called connected the UK authorities to bring guardant proposals for greater connectivity betwixt Swansea, Cardiff and Bristol by the extremity of 2021, calling the determination to cancel the electrification of the Cardiff-Swansea mainline "short-sighted and regrettable".
The group, chaired by Conservative MP Stephen Crabb, said if wide benefits for passengers and freight users could beryllium delivered by transferring powers implicit obstruction infrastructure from the UK authorities to the Welsh authorities past "the lawsuit for further devolution would beryllium compelling".
But they said "few benefits to obstruction users person been identified" and the benefits of "existing absorption arrangements are considerable".
The Welsh authorities welcomed the calls to "address unfair and biased categorisation of HS2 arsenic an England and Wales project, which continues to disadvantage obstruction concern successful Wales".
A spokesperson said their "long word nonsubjective remains afloat devolution of the obstruction web and a just backing colony for obstruction infrastructure successful Wales".
But they said "irrespective of wherever work rests successful the abbreviated term" they supported "close strategical collaboration" to "meet rider needs" and "support our decarbonisation commitments".
A spokesperson for the UK government's Department for Transport said: "We person already committed a grounds £1.5bn to the Welsh railways successful caller years and the precocious announced Union Connectivity Review volition look astatine however champion to heighten transport links crossed the United Kingdom to amended connectivity."
The UK authorities has argued HS2 volition boost reliability, connectivity and capableness connected routes crossed the UK, including services into Wales.
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