A trade union has accused Irn-Bru maker A.G Barr of 'anti-union' tactics which it said were "potentially illegal".

Truck and shunter drivers at the company's plant in Cumbernauld are engaged in strike action having rejected a 5% pay increase.

On every Friday from 11 August to 6 October around a dozen Unite members at the factory will strike, with another round to begin at midnight on August 25.

However, the union has accused A.G Barr of potential use of agency labour to circumvent the strike, and said it has reported A.G. Barr and the contractors - Stobbart and Streamline - to the Department for Business and Trade.

The Herald: File photo dated 9/9/2011 of bottles of Irn Bru in the production hall at AG Barr's Irn Bru factory in Cumbernauld. The Scottish drinks company has said it is seeing encouraging trading as people return to restaurants, pubs and bars around the UK.

Under The Conduct of Employment Agencies and Employment Businesses Regulations 2003, it is a criminal offence for employment agencies to supply labour to employers specifically for the purposes of covering work normally carried out by employees who are taking part in lawful industrial action.

Unite general secretary Sharon Graham, said: “A.G. Barr’s behaviour during this pay dispute has been disgraceful. The company is on the brink of forever tarnishing its reputation with not only the workers but the Scottish public.

“A.G. Barr is displaying nasty anti-union tactics in an attempt to bully and intimidate our members back to work. Unite will not tolerate this behaviour and we will challenge it head-on in the defence of our members’ jobs, pay and conditions.”

Read More: Irn-Bru shortage feared as A.G Barr. strike dates announced

The soft drink company increased its revenue by 18.2 per cent to £317.6m for the year ended on 29 January 2023, and posted £43.5m in adjusted profit before tax.

A.G. Barr chief executive, Roger White, will retire in the next 12 months and Unite said the pay dispute could be settled at a cost amounting to a fraction of his last bonus payout of £462,000.

Andy Brown, Unite industrial officer said: “A.G. Barr’s conduct during Unite’s pay dispute has left a very sour taste in the mouths of our members. How the CEO, Mr White, can even begin to say with a straight face that our members don’t deserve more than five per cent when he has a remuneration package totalling nearly £1.8m is ludicrous.

“Our members will continue to fight for fair pay at A.G. Barr, and they deserve the Scottish public’s support in fighting back against corporate greed.”

A spokesperson for A.G Barr said: "We strongly refute the provocative accusations by Unite the union that we have potentially engaged in illegal activity during industrial action. This is untrue and strongly denied. We respect our drivers’ decision to take industrial action, which is their personal choice. We have done nothing to deter or intimidate them.  

"We note that Unite has apparently made a report to the Department of Business and Trade. We will of course co-operate in any investigation to provide the necessary evidence.”