Sir Keir Starmer insisted Wales has “enormous untapped potential ready to be unleashed” as he prepares to complete his UK tour.
The Prime Minister will attend the Senedd in Cardiff and hold talks with First Minister Vaughan Gething on Monday.
His visit to the Welsh Parliament is part of a whistlestop tour also taking in Scotland and Northern Ireland as he pursues an “immediate reset” of the relationship between the Westminster Government and devolved nations.
“Working in lockstep with the Welsh Government and Vaughan, my Government will place the people and communities of Wales front and centre as we move towards a decade of national renewal.
“That means turning the page on years of economic hardship, towards genuine shared prosperity for working people, so they see and feel real tangible change in their lives.”
Sir Keir campaigned alongside the embattled First Minister during the General Election.
Mr Gething has faced calls to quit after he lost a no-confidence vote last month.
It came following the collapse of the co-operation deal between Labour and Plaid Cymru and a series of rows involving Mr Gething.
Mr ap Iorwerth wrote: “We welcome your statement of intent to reset the relationship between the UK Government and the Welsh Government; however, this cannot be achieved unless the views of elected representatives in Wales are respected.
“Where there is historical discrepancy between members of the Welsh Government and now UK Government on issues such as the devolution of the Crown Estates, the devolution of justice and policing, HS2 consequentials, and a fair funding formula for Wales, we would welcome early clarification on your position going forward.
“Wales’s ability to prosper is reliant on having the necessary funding and powers to create a fairer economy that is able to adequately resource our public services.”