Image copyright Getty Images Image caption A dispute over the role of guards on trains has continued for more than a year

Southern rail has axed a quarter of its train services as an overtime ban by driver's union Aslef comes into force.

Aslef is in dispute with Southern over driver-only-operated trains and the role of train staff.

Mick Whelan, the union's general secretary, said: "The ban reflects the total loss of trust and goodwill between train drivers and the company."

Southern is operating a revised timetable affecting services in Kent, Sussex, Surrey and Hampshire.

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Timetable changes

Southern says full details of changes to services will be on its website throughout the latest overtime ban.

There are no off-peak Gatwick Express services between Brighton and the airport - a limited peak service will operate, Southern said.

There are also no direct services between London and both Southampton and Portsmouth - passengers will need to change trains on route.

No trains will run between East Croydon and Milton Keynes via Kensington Olympia.

The company said it expects to run "significantly more services" from Monday.

Southern Passenger Services Director Angie Doll said: "This action is going to be very inconvenient to our passengers and communities but by putting in this revised timetable we will be able to run a more reliable and consistent service."

Pay talks

The drivers' union has been in the dispute with Southern and its parent company Govia Thameslink Railway (GTR) over the roles of train staff.

GTR replaced conductors with "on-board supervisors" to work across different services but without the responsibility of closing doors - which has switched to train drivers.

The overtime ban had been due to start on 4 June but was postponed while fresh talks were held. The union and train company have been discussing drivers terms and conditions, industrial relations and pay in parallel negotiations.

Image copyright Bradley Rees Image caption The Association of British Commuters is campaigning for a judicial review into the government's handling of the Southern franchise

The Association of British Commuters (ABC) is attending a hearing at the Royal Courts of Justice later in its bid for a judicial review of the government's handling of the Southern rail "fiasco".

Summer Dean, of ABC, said: "Passengers are the only people who still don't have a voice in this fiasco, and many thousands of them support us in our efforts to reveal the truth behind the Department for Transport's involvement in Southern Rail."

ABC said ministers acted unlawfully by failing to determine whether managers had breached franchise obligations.