Clydesdale and Yorkshire Bank is to close 79 branches with the loss of more than 400 jobs, according to Unite.

The union said the decision to close a third of the bank's branch network will be "deeply devastating" to the employees.

It is the largest-ever closure plan by the company and will radically change the face of the bank, according to Unite.

National officer Rob MacGregor said: "Staff across the Clydesdale and Yorkshire Bank will be devastated to learn that 79 branches will close and consequently over 400 colleagues will lose their jobs.

"Unite is clear that the closure of a third of the bank's branches will not only be concerning for staff but the local communities which will see their bank branch close.

"This cost-cutting plan leaves customers with less choice for local banking.

"The union has called on the bank to give a commitment to mitigate compulsory redundancies where possible and that they will reconsider closing any bank branches that are the last bank in a town.

"Unite workplace representatives will be able to assist members over the coming day and weeks to support staff impacted by this announcement."

Clydesdale said, since 2011, the number of customers using their bank for day-to-day transactions across the banking industry in the UK has fallen by a third.

A statement said: "This ongoing decline in branch usage, married to a sharp and sustained increase in digital and mobile engagement, has driven a shift to providing greater access to day-to-day banking services remotely, on the move and outside of normal business hours.

"The Bank continues to reshape its service offering in response to these changing needs.

"To support this transformation the Bank is committing £350 million over the next two years, embracing digital innovation while continuing to invest in a more sustainable branch network to deliver a superior customer experience.

"The Bank's first priority is to our customers and we will be working extensively with impacted customers, local communities and relevant stakeholders to ensure that the transition to their new branch is as smooth and as sensitive as possible, particularly where vulnerable customers are concerned.

"It is also the Bank's intention to try to find roles for frontline branch staff either within other branches or elsewhere in the Bank, wherever possible.

"However, there will inevitably be employee number reductions as a result of these changes.

"We anticipate that around 200 Clydesdale Bank staff will be at risk of redundancy and subject to our redeployment process.

"All employees affected by these changes will be fully supported through the process."

Gavin Opperman, customer banking director, Clydesdale Bank, said: "While the decision to close any branch is never an easy one, it is important that we, in line with other banks operating in the UK market, continue to respond to changes in the way customers want to bank with us.

"The changes announced today continue our journey towards a model that combines an enhanced digital platform with a right sized branch network; allowing customers to interact with us through a wide range of channels - mobile, online, telephone, in-branch - whenever and however they want."

The company said about 200 Clydesdale Bank staff will be at risk of redundancy and subject to its redeployment process.

Separately, about 200 Yorkshire Bank staff will be at risk of redundancy.

Scottish Conservative shadow economy secretary Dean Lockhart said: "Coming on the back of today's rise in unemployment in Scotland, this represents further troubling news for our labour market.

"We trust that Clydesdale will do all it can to limit redundancies and ensure staff are given the clarity they deserve about the future."

Unite has published a list of the branches expected to close:

Clydesdale Bank

Aberdeen Riverside, Aberlour, Aboyne, Alloa, Banff, Bathgate, Bearsden, Beith, Bellshill, Brechin, Buckie, Cambuslang, Castle Douglas, Cumnock, Dalkeith, Dunoon, East Kilbride Stuart Street, Edinburgh Leith Walk, Edinburgh University, Forfar, Fraserburgh, Giffnock, Glasgow Aikenhead Road, Glasgow Bath Street, Glasgow Charing Cross, Grangemouth, Johnstone, Leith, Leven, Mintlaw, Renfrew, Rosyth, Rothesay, Saltcoats, South Queensferry, Stonehaven, Stranraer, Thurso, Tillicoultry and Troon.

Yorkshire Bank 

Alfreton, Barnoldswick, Bradford West Bowling, Burton-Upon-Trent, Chadderton, Cleveleys, Clitheroe, Coalville, Crewe, Filey, Gateshead, Goole, Guisborough, Hinckley, Hull Hessle Road, Knottingley, Leamington Spa, Leeds Central, Leeds Chapel Allerton, Leeds Headingley, Leeds Woodsley Road, Leigh, Middlesbrough Berwick Hills, Newark, Normanton, Norton, Nottingham Bulwell, Ossett, Pickering, Retford, Richmond, Ripon, Royton, Sheffield Broomhill, Sheffield Firth Park, South Shields, Todmorden, Wath upon Dearne and Wellingborough.