According to Unite, the influence of government commissioners at the city council is hampering negotiations to end the industrial action, which began in January.

Staff are striking over the authority’s plans to scrap the role of waste recycling and collection officer, which Unite claims would mean pay cuts of up to £8,000 for 150 workers.

Unite general secretary Sharon Graham said: ‘At the moment, the commissioners seem to be blindly imposing the last government’s slash and burn policies against Birmingham and it is just making things worse.

‘Ministers should now step in. Cutting vital public services to the bone and victimising workers is not what Labour was elected to do.’

The dispute has shown no sign of letting off, with industrial action recently extended from eight to 25 days over February and March, and striking staff rejecting a cash offer from the council.

Birmingham said it was ‘incredibly disappointing’ that workers had rejected the council’s ‘fair and reasonable’ offer.

A council spokesperson said: ‘The continuance of industrial action will inevitably mean yet more disruption to residents at even greater expense to the taxpayer. Our door is still open, and we would urge Unite to come back to the table.’

Unite national lead officer Onay Kasab also claimed that recycling in Birmingham was ‘almost non-existent – not because of the strikes but because the lorries don’t work’.

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