Geraint Davies, Swansea West MP, has joined with fellow Welsh MPs to urge the Chancellor to support the Welsh economy following Covid-19.
The letter highlights a report about how local economies will be impacted by the Covid-19 crisis.
The research ranks towns according their economic vulnerability and finds that 40% of the top 50 most vulnerable towns are in Wales.
Mr Davies said: “This report demonstrates just how vulnerable Wales is to the economic shocks that Covid-19 is delivering.
“Wales is likely to be the United Kingdom’s most affected region, with coalfield towns and towns with industrial economies particularly hard hit.
“With many Swansea residents working in or connected to the Port Talbot steelworks this report is particularly worrying for many of my constituents.”
In 2018 the Government promised to launch a consultation on the Shared Prosperity Fund (SPF) before the end of that year, which was intended to look at opportunities for economic growth and regional funding following the UK’s departure from the European Union.
Mr Davies said: “It is concerning that in the most recent budget the Shared Prosperity Fund was not even mentioned.
“That is why this letter is asking the government to bring forward a consultation on the SPF to ensure that the local economies hit hardest by Covid-19 are given the support and investment they need.”