SIPTU is hoping to convince the Japanese firm NEC to reverse the closure of its Co Meath factory during talks in London today.
The company announced this week that it would be closing the Ballivor plant in September and transferring its business to lower cost locations in Asia.
Three hundred and fifty workers are set to lose their jobs as a result.
SIPTU is due to meet senior NEC management in London today to discuss the situation and has said it is still holding out hope that the company may reverse its decision or at least save some of the 350 jobs.
Communications Minister Noel Dempsey, a TD for Co Meath, is also due to attend the talks.