With just two months left until Christmas, members of the Communication Workers Union (CWU) who work for Royal Mail have been voting on whether to launch a campaign of action. The result will be announced on Tuesday, with expectations of a yes vote among the union's 110,000 members involved in the row. The CWU says that Royal Mail is not sticking to an agreement reached last year covering a wide range of issues, including plans to reduce the working week, as well as job security. Industrial relations at the company have worsened this year, with widespread unofficial strikes breaking out virtually every week. "We face an assault on our terms, conditions and national agreements like we have never seen before. I am confident our members will stand with the union and delivery a massive yes vote in what is the most important dispute the union has ever had," he said. Shane O'Riordain, the Royal Mail's managing director of regulation and corporate affairs, said there were no grounds for industrial action. He said: "We remain committed to open and constructive engagement with the CWU. We all want a successful and sustainable company that provides good quality jobs, fairness in workloads, and continues delivering a sustainable Universal Service. "No industrial action can be taken before the conclusion of our mediation period. We will continue to engage in the agreed dispute resolution processes set out in the Agenda for Growth. "Industrial action - or the threat of it - undermines the trust of our customers. It makes it harder for Royal Mail to pay for the existing industry-leading terms and conditions it provides." He said Royal Mail was honouring the 2018 agreement. Since it was put in place there have been two pay increases of 5% and 2%, the working week had been cut by an hour, and the company was working with the CWU to lobby the Government for a new pension scheme. He added: "We have announced a transformation plan, through which we want to invest £1.8 billion over five years to return our UK business to growth. Hardly any UK companies are making that kind of investment right now." For unlimited access to Scotland’s best news, sport and expert analysis, SUBSCRIBE to The Scotsman website here