The UK's last remaining independent savings bank is to close down.

Airdrie Savings Bank, founded in 1835, operates two branches in Lanarkshire and a head office in Airdrie but confirmed on Wednesday it will be ending all business activities.

The bank will close its branches in Coatbridge and Bellshill on April 28 as part of a phased shut down of operations, with up to 70 staff likely to lose their jobs.

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All current accounts will close on April 28 while the head office will remain open for as long as is needed for customers to transfer their money to an alternative banking provider.

It is thought that process could take until the end of the year.

The bank is understood to have about 10,000 current accounts and 30,000 deposit accounts.

Chairman Jeremy Brettell said: "Whilst we are financially strong, a comprehensive strategic review of all future options concluded that we will not have - as a very small bank - the resources in the years ahead to provide the products and services our customers need in this increasingly digital world.

"The decision to implement a phased end-of-business activities is totally consistent with the over-riding responsibility of our Board of Trustees to protect the best interests of our customers, both now and in the future."

Chief executive Rod Ashley attributed the closure to a backdrop of several previous branch closures in recent years, a shrinking customer base, declining footfall and an ongoing escalation of operating costs.

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Mr Ashley said: "Sad as the course of action outlined today is - in terms of our history and heritage - we are in absolutely no doubt it is in the best future interests of our customers."

All of ASB's portfolio of secured loans and mortgages will be transferred to TSB as part of a newly-established business relationship, Mr Ashley confirmed.

He added: "We identified TSB as a bank with a similar ethos and culture to our own and approached them for support in offering our customers security and continuity as we prepare for a phased end to our business activities."

In the first instance, this will involve customers' secured loans and mortgages being transferred automatically to TSB.

Mr Ashley went on: "For customers who hold savings and current accounts with us, we will offer support to help them close their accounts and transfer their banking business to an alternative financial-services provider of their choice.

"That may be TSB or it could be any another bank or building society. Either way, we will be there with them - in person, on the telephone or online - to help them transfer their business easily and quickly."

The Unite trade union said it was a "bitter disappointment" to see the bank close, attributing it to a "wider crisis" in the Scottish banking sector.

Regional officer Wendy Dunsmore said: "Unite will be doing everything we can to support our Airdrie Savings Bank members during this incredibly sad and difficult time, and to make sure their employment rights are protected.

"Airdrie Savings Bank has become yet another innocent victim of casino bankers.

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"Even at this late stage, we would urge the Scottish and UK governments and the banking regulators to work with us to explore all options for saving jobs."

The Financial Conduct Authority, Prudential Regulation Authority and the Scottish Government have been informed of all arrangements.

Airdrie and Shotts MSP Alex Neil expressed his "deep sorrow" at the closure.

Mr Neil said: "The Airdrie Savings Bank (ASB) has been an institution for 182 years.

"It has served the people of Lanarkshire well for all that time. After the financial crash of 2008, it was probably for a while one of the few viable banks left in Britain.

"Up to 70 people will lose their jobs over the next few months and I, along with Neil Gray MP, will be doing all I can to ensure that every possible effort is made to help these good people find alternative employment.

"It should be stressed that nobody's money is at risk. All those with savings with the ASB will get back every penny that they have in the bank."

A Scottish Government spokesman said: "Sadly, Airdrie Savings Bank advises that it is no longer able to compete in a changed banking world and the board has made the difficult decision to wind down now, in a controlled and orderly manner, thereby protecting customer deposits.

"This reflects the bank's prudent, careful approach to banking, which has served their local community well over many years and which will be sadly missed.

"Neither the Scottish nor UK governments are able to intervene to 'rescue' the bank as direct intervention is prevented by state aid rules on aid to the banking sector.

"However, the Scottish Government's Partnership Action for Continuing Employment (PACE) will offer appropriate support to staff affected by this announcement.

"We understand TSB will share local vacancies with staff and welcome applications."