A strike at a Ministry of Defence missile depot in Beith "cannot be allowed to carry on", according to union officials.
More than 50 members of the GMB union at the Defence Equipment & Support (DES) munitions depot in the town walked out this morning.
It comes after 93 per cent of GMB members at the depot voted for strike action over a dispute on retention bonuses.
Managers and craft workers are in receipt of bonuses whilst non-craft workers do not, meaning non-craft workers get less than many supermarket workers.
DES is an arm’s length body of the Ministry of Defence which delivers equipment and support services to the UK armed forces.
Chris Kennedy, GMB Scotland organiser, said: “These workers are utterly vital to the UK armed forces – they deserve to be recognised as such.
“Instead, management have allowed a two tier workforce to develop, fostering bitterness and anger among workers.
“Today’s strike is the first in the history of the DES – it cannot be allowed to carry on.
“If the Defence Secretary does not step in to right this wrong, supplies of the crucial missiles manufactured at Beith will soon run low.”
The union says it wrote to UK Defence Secretary, Ben Wallace MP, in June to call for his intervention, but have received no reply.
Last month, GMB Scotland representatives met with DES management to seek parity between non-craft members and their craft worker counterparts.
Despite these negotiations, the union says, no satisfactory resolution was reached, leading to the decision to proceed with industrial action, with workers walking out last Friday and today (Monday July 17).
An MoD spokesman said: "Pre-planned contingency measures are being implemented at Defence Munitions Beith to ensure the continued operation of the site.
"We remain open to dialogue with GMB to discuss the issues raised and work towards resolving them."
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