Rail workers are to be balloted on industrial action over a dispute with the new operator of the Caledonian Sleeper service.

The RMT union claims operator Serco has failed to address "potentially dangerous" defects in the rolling stock of the London to Scotland overnight service.

The decision to ballot its members follows several meetings with the company's senior managers over the last few months.

The union's general secretary Mick Cash said: "The poor service to passengers, in conjunction with the company's failure to address the issues raised by RMT representatives and officials over several months, has now reached the point where the union has decided enough is enough and we will now proceed to ballot for industrial action before someone is injured."

The sleeper franchise was awarded to Serco by the Scottish Government in 2014, with the company taking over from March this year.

Mr Cash added: "Our members have been unhappy with Serco's management of the iconic service from Scotland to London since the very early days of them taking on this 15-year franchise.

"This is yet another example of Serco winning public sector contracts and failing to deliver for the taxpayer, passengers and staff. "

Peter Strachan, managing director of Caledonian Sleeper, said: "We are disappointed the RMT is considering industrial action and are absolutely committed to continued dialogue with our employees and their representatives.

"Since taking over running of the Caledonian Sleeper eight months ago Serco has worked hard to improve the service for both our customers and staff."