TALKS are under way in a bid to avert a strike planned for Friday involving CrossCountry onboard staff and separate action affecting ScotRail over the coming weekend. But Christmas disruption still seems set to go ahead on London Underground.

The executive committee of the RMT is considering a fresh offer from ScotRail in a dispute about the sacking of a ticket examiner. The union had called two one-day strikes for Saturday and Monday, claiming that the dismissal of Scott Lewis had been unfair.

Mr Lewis had been involved in an argument with a passenger travelling to Prestwick Airport using a free ticket issued by an airline. The passenger involved later said he had been made to feel 'like a criminal', but that even so he did not want Mr Lewis to be sacked.

ScotRail confirmed that fresh discussions had been taking place. A spokesman said: "Constructive dialogue has taken place with the RMT to avert strike action next weekend and to end the dispute. It is hoped there will be a successful outcome."

Scottish transport minister Keith Brown revealed he had become involved in the talks, and urged both sides to continue negotiating 'in this positive vein'.

Meanwhile, CrossCountry said it had been holding its own 'constructive' discussions with the RMT over a planned walkout on Friday, which was called after the RMT claimed that industrial relations at the company had broken down, while Network Rail said it did not expect First Capital Connect and East Midlands Trains services to St Pancras International to be affected today by a strike by signallers at West Hampstead.

However, London Underground services are still likely to be disrupted on Boxing Day, with Aslef drivers set to walk out in a dispute over payments for Christmas working.