Andy Burnham has warned a major London commuter rail company that it must improve its services after a summer of delays, disruption and cancellations.
South Western Railway was the first train firm to be taken back into public ownership by the Labour Government.
But passengers have suffered months of disruption on the commuter route for the capital, as they have on other rail services around the country, partly due to the series of heatwaves.
The Prime Minister told how he is going to summon rail chiefs to to try to improve rail services under the Government’s nationalisation programme.
He is to host a rail summit later this year amid growing questions over the benefits of bringing rail firms back into public ownership.
During a round of regional media interviews the Prime Minister was asked about the services this summer on South Western Railway after the disruption.
The former Mayor of Greater Manchester told BBC South: “It will get better.
“I have experience of taking over public transport and then using that public control to deliver public benefit and I would be the first to acknowledge that the railways aren't there yet and we need to get our hands on it, a grip on it….and change the way the railways are working.
“We've had a difficult summer across the railway network, across all of England and the UK, to be honest.
“It isn't good enough.”
The new Prime Minister added: “I think there's a long hangover from privatisation, if I'm honest with you.
“It led to high fragmentation, a breakdown in relations between the staff running the system and the management. The railways are in need of repair and that will take some time.
“I realise passengers can't wait forever, that's why I'm calling a rail summit for later this year to get underneath all of these issues, get a grip on the problems and also start to make rail travel more affordable for people too.”
A number of other rail companies had worse cancellation levels this summer than South Western Railway, with the highest proportion on Avanti West Coast, followed by CrossCountry and London Overground, according to analysis of data from the Office of Rail and Road.
The PM’s intervention came on the same day that Lord Sadiq Khan announced he was putting some London buses back into public ownership for the first time in 30 years.
South Western Railway last week launched Improving Your Railway, acknowledging recent challenges and setting out its short, medium and long-term plans to deliver a more reliable railway.