Eight Yorkshire MPs are part of a group of 124 parliamentarians who have urged Barclays to reverse its decision to end over-the-counter cash withdrawals for customers from Post Office branches from next year.
In a letter to Barclays chief executive Jes Staley, the cross-party group call for the bank to help end the "cash crisis" facing their constituents.
The MPs, who include Clive Betts, Tracy Brabin, Nic Dakin, Holly Lynch, Paula Sherriff, Kevin Hollinrake, Angela Smith, and Alex Sobel, fear the bank's decision, which was announced last week, will hit the most vulnerable communities the hardest.
Rachel Reeves did not sign the letter but previously said the decision would be “terrible for customers and for our post office network” and urged Barclays to make a U-turn.
Pressure has been mounting on Barclays since it emerged that it will stop allowing its customers to make cash withdrawals from Post Office branches from January 8, 2020.
Around 15m cash withdrawals were made by Barclays customers through the Post Office last year.
Some five million cash deposits were also made - although Barclays is remaining in the cash deposit part of the Post Office's framework.
The letter was co-ordinated by Chris Elmore, Labour MP for Ogmore in Wales, and is supported by MPs including former Commons leader Mel Stride and shadow economic secretary to the Treasury Jonathan Reynolds.
It reads: "This change will only add to the cash crisis many of the most vulnerable and elderly in our communities are currently facing.
"We would strongly urge you to reverse this decision to prevent your customers - and our constituents - from being left behind in the wake of the banking sector's digitisation."
The letter says Barclays' decision "sends a message - rightly or wrongly - that those who cannot properly access the digital economy will have the carpet dragged from under their feet as our high street banks continue to abandon the communities that have sustained them for decades".
A range of groups have already expressed strong concerns.
The Treasury Committee has previously said Barclays' move is "hugely disappointing", adding that "the use of cash cannot be left to wither on the vine".
Consumer group Which? recently found that Barclays had closed 481 branches - around a third of its network - between the start of 2015 and August 2019.
Which? money editor Jenny Ross previously said: "Barclays' shocking decision exposes the fragility of the UK's cash system."
The Payment Systems Regulator (PSR) has said it will be "closely monitoring" the steps Barclays plans to take.
In the letter, the MPs offer to meet Mr Staley to discuss their concerns in person, adding: "We look forward to hearing from you as a matter of urgency."
Barclays' customers will still be able to access other services such as continuing to deposit cash and cheques at the Post Office after this date.
Other banks have agreed to maintain the full range of services they currently offer through the Post Office.
Barclays has also announced that it plans to introduce a cashback scheme from next year involving small businesses, and has pledged not to close branches in remote areas or where it is the last bank in town for the next two years.
Post Office banking services director Martin Kearsley said: "We understand why customers and many others are so worried and disappointed by Barclays' decision.
"We share this disappointment because we are committed to delivering key everyday services to as many customers as possible.
"Our free cash withdrawal service for customers of UK banks is a real lifeline for millions of customers in communities across the country.
"We are delighted that 27 banks have recognised that our network of over 11,500 branches, 6,000 of which are in rural areas, offers by far the best solution for easy access to vital cash withdrawals wherever people live in the UK."