Train drivers on Southern Railway have voted to strike in a dispute over driver-only trains.

This means the threat of increased disruption to services in the run-up to Christmas, as increased.

Members of ASLEF, the UK union for train drivers and operators, supported walkouts by 87%, and other forms of action by 95%. The turnout was 77%.

The row is separate from the long-running dispute between Southern and the Rail, Maritime and Transport union over changes to the role of conductors.

ASLEF accused the company of wanting to impose changes rather than reach an agreement.

General Secretary Mick Whelan said: "Our trade dispute with the company is that there should be no introduction and/or extension of new driver-only operated routes on Southern without the agreement of Aslef.

"We have genuinely sought to reach a compromise with Southern.

"We have always been prepared to talk to the company and we have always been of the view that it should be possible to do a deal, but it takes two to tango and the company has not been prepared to negotiate.

"They have dug in their heels and forced us to ballot our members."

The union will have to give seven days’ notice of any industrial action.

Members of the RMT have staged a series of strikes on Southern in recent months, with three-day walkouts due to start on December 6, 22 and 31.

Southern services are also being disrupted on other days because of issues including a shortage of staff.

Charles Horton, chief executive of Southern's owners, Govia Thameslink Railway, said: "It's perfectly safe for the driver to have sole responsibility for the operation of a modern train, and that's how a third of the trains up and down the country - with the full agreement and support of Aslef - already operate today.

"The travelling public has already suffered months of misery and hardship as a result of the RMT's pointless series of strikes.

"We urge Aslef to get round the table with us to continue our talks and resolve their dispute without causing further unnecessary grief to passengers."

Mr Whelan told MPs that it had been their policy for more than 15 years to seek to eradicate driver-only operation (DOO).

He said: “DOO was designed for three-car 317s on the Bed-Pan (Bedford to St Pancras) line in the early 1980s when it was all about managed decline at the fag end of British Rail.

"An increase in the number of passengers we are carrying every day means you have 1,100 passengers on a 12-car train and just two seconds to check 24 sets of doors, and that's simply not adequate to deal safely and properly with the travelling public.

"The difference between us, and the Department for Transport, and companies like Southern, is that we're honourable.

"Where we have agreements we work to those agreements, even when we are seeking to change them, because we think they're inherently unsafe.”