Map reveals mayor's London Overground rail takeover plan

The feint orange line reveals which routes the Mayor of London wants to take over

A new map revealing how London could look if the mayor took over the running of suburban rail services has been released by Transport for London (TfL).

Sadiq Khan will set out a business case for services running into the capital to be devolved to TfL.

He claims it would improve passenger service and tackle delays and overcrowding.

TfL's board will consider the proposals on Thursday before seeking approval from the government to move forward.

The first franchises up for renewal - services in southeast London and Kent - will be this autumn with further franchises involving South West Trains, Southeastern and Govia Thameslink Railway due for renewal by 2021.

Analysis by Tom Edwards, BBC London transport correspondent

Every mayor so far has wanted more control over suburban rail services and Sadiq Khan is no different.

Certainly beleaguered commuters and politicians of all ilks, including Kent County Council, want TfL to control their lines using the concession model where TfL pays an operator to run the service (like the Overground).

There are sticking points though - the politics. This is a Conservative government and a Labour Mayor. How can TfL run services outside the area of jurisdiction? (Clue: look at the Met line). And capacity - lines into places like Waterloo are already full; whoever runs it and Network Rail will still control the infrastructure.

And TfL can only take over when contracts come up. So while the intentions are clear, this won't happen overnight.

Mr Khan said: "Passengers on London's suburban rail routes simply aren't getting a good enough service. They face increasing rail fares year after year, yet face daily delays, cancellations and overcrowding.

"Ahead of the Autumn Statement, I'm looking forward to presenting the full business case for how a transformed and modernised suburban rail network could also unlock new homes and provide other substantial economic benefits for London."

Earlier this year think tank Centre for London called on the Department for Transport to devolve the network due to "strained" rail services in south London.

When it was first raised the Rail Delivery Group, which represents train operators and Network Rail, said the current system produced some of "the best passenger satisfaction levels".