The fashion giant is understood to be moving the production of polo shirts to an American factory, causing uproar in the Welsh town of Treorchy.
GMB senior organiser Mervyn Burnett said the unions are not ruling out legal action and criticised Burberry's handling of the proposal. 'GMB is shocked and disappointed that a company we have worked with for over 30 years gave no notice to GMB or our members that this announcement was under consideration,' he said.
'GMB has since met the company and we have conveyed to it that the union and its members are absolutely appalled and totally condemn this way of doing business.'
However, Burberry said that, following a year-long review of the factory, it was found to be no longer commercially viable. The brand stressed that the proposal to close the factory was not a reflection of Burberry's commitment to the UK market.
GMB said it will not rule out applications to an Employment Tribunal and that it will be contacting elected representatives in local government, the Welsh Assembly, Westminster and the European Union to fight the proposal.