UNION leaders have called for fresh talks on the train guards dispute as hundreds of thousands of passengers faced a second day of disruption because of strike action.

The Rail, Maritime and Transport union (RMT) said its members on South Western Railway (SWR) were "standing firm" on the second of 27 planned strikes which is leading to hundreds of services being cancelled.

READ MORE: South Western Railway: Company issues statement ahead of month-long strike

A signal failure between Fulwell and Shepperton on Tuesday caused more delays.

Passengers were told that services running to and from these stations may be cancelled, delayed or changed at short notice, with disruption expected until 12 noon.

READ MORE: South Western Railway strike: Timetable available

RMT general secretary Mick Cash said: "Our members are solidly supporting the second day of this phase of strike action and are standing firm the length and breadth of the franchise in defence of the role of the guard, accessibility and the safest method of train dispatch and operation.

"It is frankly ludicrous for the company to simply jam their heads in the sand rather than getting back round the table to get the same deal back on track that they pulled away from at the last minute in earlier negotiations.

"A deal is there to be done which would cost the company nothing and which would give the safety and accessibility guarantees at the platform/train interface that we have been seeking. SWR need to get out of the bunker and get back into talks."

The company said it has given the union guarantees about having guards on its trains.

An SWR spokesman said: "We are always open to talks if the RMT is ready to work with us to improve our service and develop a more visible, customer-focused role for guards."