Southern Rail is to cut 341 trains a day as it revises its timetable to respond to prolonged cancellations and delays.
The new schedule, which allows the cancellation of 15 per cent of trains, will start on Monday amid growing tension with RMT union, which has said the firm is in "crisis management".
Southern Passenger Services Director Alex Foulds said: “We are introducing this temporary weekday revised timetable with reluctance but it is the best thing we can do for our passengers who have been suffering daily cancellations ever since this dispute with the RMT began, and for which we are sincerely sorry.
“It should give the majority of our passengers a better, more consistent service that they can plan around.
“Whilst our first priority is our passengers, we also understand that this has been a difficult time for our staff. Conductors already know that their jobs are guaranteed, that there will be no reduction in salary and that the independent rail safety body has confirmed our plans are safe.
“Now, after listening to our staff, we have also decided to restore leisure travel benefits. All of this, we believe, should help our staff feel able to return to work and so reduce the issues causing the current high level of train cancellations.”
The revised temporary weekday timetable will run until train crew availability returns to normal.
Southern is the brand name used by GTR on the Southern routes of the Thameslink, Southern and Great Northern franchise.
GTR is at loggerheads with the union over plans to move toward more driver-only operated services, with the union opposed and Southern stating it is taking action to get staff back to work.
In recent weeks there has been industrial action as well as prevalent staff sickness. RMT has said that the sickness is unofficial industrial action.
But RMT General Secretary Mick Cash said: "This is crisis management on Britain's biggest rail franchise, a franchise that is now in terminal meltdown. The continuing attempt to blame this gross mismanagement on the front line staff is a cynical and cowardly ploy by a company who have chosen to wage war on their passengers and workforce alike."
“The managers at GTR pay themselves fat salaries and bonuses, in reward for failure on an epic scale, while the staff on the trains and platforms are left to take the blame for the bosses incompetence.
“This so called emergency timetable enables Govia to cancel 15 per cent of their trains and rig their appalling performance figures to protect their profits.
“Instead of conniving with this scandal the government should fire GTR and immediately instruct the legal, public-sector fall-back operation to take over.”
RMT said that the dispute by the RMT is entirely unnecessary, as the RMT’s officials have already admitted, there will be no job losses, and no-one will take a cut in salary.
Foulds added: “Once again, we urge RMT officials to relax their unbending attitude to our plans and to step over the line in the sand they have drawn opposing any extension of driver-only train operation.”