TRAIN services are set to be crippled across Sussex after the owners of Southern Railway lost a legal bid to halt a series of strikes by train drivers.

Members of Aslef will walk out for three days next week and six days in January in a bitter dispute over driver-only trains, which will halt all Southern services, causing more travel chaos for hundreds of thousands of passengers.

Govia Thameslink Railway (GTR) argued in the High Court the action would unlawfully restrict freedom of movement provisions under EU law, but judge Sir Michael Burton refused to grant an injunction blocking the strikes.

Southern now faces an escalation of industrial action following months of strikes by members of the Rail, Maritime and Transport union in a separate dispute over changes to the role of conductors. The latest RMT stoppages ended last night, with another 48-hour strike due from December 19 and a three-day walkout from New Year's Eve.

Drivers will strike next Tuesday, Wednesday and Friday, bringing services to a standstill. Aslef members launched an overtime ban earlier this week, which, coupled with the RMT strikes, led to the cancellation of around half of Southern's services.

Aslef general secretary Mick Whelan said: "Now the company should do the right thing and sit down with us and negotiate to do a deal for the benefit of passengers, staff and the company."

Mr Whelan said driver-only operation (DOO) is "inherently unsafe", adding: "DOO is old technology, designed in the early 1980s at the fag end of British Rail when everything was about managed decline.

"We have seen an increase in the number of passengers we are carrying on the railway every day. We now have 1,100 passengers on a 12-car train and two seconds to check 24 sets of doors is simply not adequate to deal, safely and properly, with the travelling public."

A spokesman for Southern said: "Naturally we're disappointed with today's decision. We will now immediately review matters with our legal team." The judge granted GTR permission to appeal. Passengers on Southern and Gatwick Express were warned to expect "severely reduced" services across much of the network from today, through the weekend and on Monday as a result of Aslef's continued overtime ban.