The group that runs strike-hit Southern rail saw profits jump by more than a quarter, as its chief executive turned down his bonus and apologised to passengers for prolonged disruptions.

Transport firm Go-Ahead said its profits leapt almost 27% to £99.8m ($132.5m) in the year to 2 July, after seeing record rail passengers across its franchise and hitting record earnings at its bus division.

The company owns 65% of Southern operator Govia Thameslink Railway (GTR) alongside French rival Keolis, which has been dogged by months of strikes, delays and cancelled trains on routes in south London, Surrey, Sussex and Kent.

Earlier this week Transport Secretary Chris Grayling unveiled a £20m fund and a new review board to improve Southern rail services and "get to grips" with problems on the network.

However, strikes are set for next week by rail union RMT over a long-running dispute over plans to move the responsibility for closing train doors at stations to drivers from conductors. The RMT opposes this move on safety grounds.

Go-Ahead chief executive David Brown said: "During this period of change, Southern services have been disrupted by restricted network capacity, strike action and increased levels of absence. We apologise to the people whose lives have been affected during this time.

"We continue to work closely with the Department for Transport, Network Rail and other suppliers and partners to operate the best service possible while delivering the long term improvements."

Southern Rail
Go-Ahead, the group that owns strike-hit Southern rail, saw annual profits jump by more than a quarter Dan Kitwood/Getty Images

Go-Ahead chairman Andrew Allner said at the group "we recognise that remuneration should be closely linked to performance". Allner added: "As a result, David Brown, who in my view is an exceptional and committed group chief executive, made it clear he does not wish to be considered for an annual bonus this year and declined a salary increase."

RMT general secretary Mick Cash said: "This profit announcement comes just a day after the Government propped up Southern with yet another £20m of taxpayers cash. The company could clearly fund improvements ‎themselves if they weren't wholly dedicated to trousering fare-payers' money in shed loads."

The group's rail division reported an adjusted profit, excluding amortisation, goodwill impairment and exceptional costs, of £57m in the year to July 2, compared to £41.7m a year earlier. Its bus unit posted a record operating profit, up 8% to £104.m on the year before.