Welsh businesses find out today how to bid for contracts worth around £10bn from Britain's largest infrastructure project.
HS2 is the high speed railway initially linking Birmingham and London.
Today HS2 Ltd's senior management team are in Cardiff.
Plaid Cymru is hoping to use today's debate on the controversial HS2 rail scheme to ensure extra money is given to Wales as a result. Jonathan Edwards MP has tabled amendments to the legislation paving the way for HS2 which will be voted on in the Commons today.
He says his amendment will be 'the last chance to enshrine in law' the principle that the Welsh Government should be receive funding equivalent to 5% of the cost of the project.
The Treasury has issued a further statement on the disagreement between Welsh and UK Governments over extra spending as a result of the HS2 rail scheme. Click here to read the background.
The Treasury now agrees that the Welsh Government HAS received a relatively small amount of extra money (£35m) because the Department for Transport's cash for HS2 came too late to change the formula used to decide how much money Wales gets.
But it's made clear the formula will be changed before there's any major spending on HS2 which means that Wales won't get any extra money if the project finally gets the go-ahead. A Treasury source described the dispute as 'overplayed.'
There are calls for Wales to have its 'fair share' of expenditure on HS2. The Welsh and UK Governments are at loggerheads over extra funding for Wales with the row focused around the HS2 rail project in England.
VIDEO: Jonathan Edwards MP, Plaid Cymru
The Welsh and UK Governments are at loggerheads over extra funding for Wales. The row centres on whether or not the Welsh Government is getting extra money as a result of the controversial HS2 rail project in England.
The Treasury's been denying that Wales is getting a share of that money. The Welsh Government insists that it has.
VIDEO: Finance Minister Jane Hutt AM
Plaid Cymru's Treasury spokesman, Jonathan Edwards MP, says that he hopes Finance Minister Jane Hutt is right in the dispute with the Treasury over extra funding as a share of spending on the HS2 rail project.
A Welsh Government spokesman has further clarified why Finance Minister Jane Hutt is sticking to her guns in a disagreement with the UK Treasury. The dispute is over whether or not Wales has received a share of spending on the controversial HS2 rail scheme.
Jane Hutt has already told ITV Cymru Wales that she stands by her claim as set out in a letter to the Finance Committee. Now a Welsh Government spokesman has underlined her position.
Finance Minister Jane Hutt is standing by her claim that the Treasury has given the Welsh Government extra money as a result of spending on the controversial HS2 rail scheme.
She'd told the Assembly's Finance Committee that £84m was passed on in the recent Spending Review as a result of Department for Transport capital spending including HS2. The Treasury has disputed that claim.
But in this short interview with Lynn Courtney, Jane Hutt insists that the money - known as Barnett Consequentials after the formula used to work out Wales' share of UK Government funds - does reflect Westminster's spending on HS2.
Money given to Wales as a result of UK Government spending on the HS2 rail project could add up to an extra £5.3bn on the total bill according to opponents of the scheme. Finance Minister Jane Hutt has acknowledged that the Welsh Government has already received a further £84m from the Treasury.
The funding is known as a 'Barnett Consequential' because it's allocated using the Barnett formula for working out the share of UK spending devolved nations should receive. The move has been welcomed by Welsh politicians for setting an important precedent.
But it's also been criticised by opponents of the whole HS2 scheme who say it adds what the call the spiralling costs of the project.