Minehead's MP says he'll be 'holding meetings urgently with senior regional officials' at Barclays over its branch closure plans.
The bank's announced the town's branch will close mid-June.
Ian Liddell-Grainger says it'll leave some customers with a two-hour round trip to Taunton or Bridgwater to visit a branch.
He said: "Barclays says its Parade branch will close in mid-June, citing a decline in customer usage as one of its reasons.
"Business and private customers were informed by letter last Friday.
"They will now need to travel to Taunton, Bridgwater or Tiverton to reach their nearest Barclays bank though officials say day-to-day transactions such as paying in or depositing cash can be done at local post offices.
"However from the contents of the letter I have received it is clear the wheels have already been put in motion.
"Barclays says 74 per cent of its Minehead branch customers now do their banking in other ways, such as over the phone or online rather than physically walking through the doors of the branch.
"But that still leaves 26 per cent who prefer to visit the bank. They are going to feel very badly let down by this and I don’t blame them."
Mr Liddell-Grainger said it was 'particularly cynical' of Barclays to write to him asking for his views as to how it could ‘smooth the transition to a new way of banking for local people post-closure’ and to ask him what he felt the impact of the closure would be.
The MP added: "The decision has already been taken and set in stone.
"Clearly Barclays doesn't care a tittle or jot about the impact on its customers and it’s entirely its responsibility to ‘smooth the transition’ - though if its local customers feel they have been betrayed and decide to effect the transition of their accounts elsewhere I can't say I would blame them.
"Barclays clearly feels the Minehead branch isn't making enough profit so it is arbitrarily removing a service that a lot of local people view as vital.
"West Somerset has one of the highest concentrations of elderly people in the country.
"Many of them don’t have or want internet access for online banking and don’t want to carry out transactions over the phone because they don't trust the system.
"If they want to stay with Barclays the only option now is going to be a two-hour round trip to Taunton or Bridgwater if they've got a car, longer if they need to use the bus - if there is a bus."
Mark Hatcliffe, Community Banking Director for Barclays Bristol, Somerset and Wiltshire, said: "The way customers undertake their banking is changing as people increasingly use online, telephone and mobile devices.
"At Barclays Minehead branch, customer usage has continued to decline and additionally nearly three quarters (74%) of our branch customers are also using other ways to do their banking such as online and by telephone.
"We hope that the availability of alternative ways of banking and access to services at the Post Office including Avenue, Alcombe and Dunster, along with our range of digital channels will help to ease the transition for our customers."