St Merryn Foods have said the packing operation at a meat processing site in Merthyr are 'no longer sustainable' - putting around 400 jobs there at risk.
The meat processing company, which employs 1100 people in total in Merthyr, say serious challenges facing the red meat sector in the UK - including declining markets, falling volumes, higher input costs and a fiercely competitive retail landscape - are to blame.
They've confirmed the decision does not impact the Beef and Lamb slaughter and cutting operations, with these continuing to operate as usual at Merthyr.
They say they'll be working with the Welsh Government, Job Centre Plus and Staffline to "seek opportunities for colleagues outside the business."
If the proposal goes ahead, jobs will be transferred to an alternative St Merryn site - most likely in Bodmin and Victoria in Cornwall.
St Merryn have confirmed this would not take place until January 2017.
Watch Hannah Thomas' report here.