The Unite union, which represents many Barclays workers, says the bank's decision to cut up to 1,700 jobs is 'a colossal mistake'.
The union said frontline roles, including cashiers, personal bankers, operational specialists, branch managers and assistant managers will go throughout 2014.
It claimed that customer service would be affected by the changes and said Barclays risked damaging its reputation.
In a statement Barclays said fewer of its customers were using branches.
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