With rail fares set to rise again by as much as 2.8 per cent, the debate over whether the UK should renationalise the railways – which Labour made a 2017 manifesto pledge – has already reared its head.

This week the Trades Union Congress renewed its call for renationalisation, saying doing so would lead to lower ticket prices.

“We’re already paying the highest ticket prices in Europe to travel on overcrowded and understaffed trains,” the organisation’s general secretary Frances O’Grady said, adding that passengers shouldn’t be “subsidising private train companies”.

But a significant proportion of the UK’s railways already are under state control, with Network Rail in charge of around 75 per cent of the industry, including the tracks, thousands of stations and signalling operations.

But what of the train operators? There are over 20 operators of franchised passenger services, and discussions about renationalising the railways generally concern returning control of these services to the state.

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But interestingly, almost all of these operators are (at least partly) state-owned already – only not by the British state.

As The Independent’s Europe correspondent (and transport aficionado) Jon Stone noted in a tweet on Wednesday, as Virgin Trains is soon reaching the end of the line, there are now few purely private operators left on UK railways.

Jon happens to be on holiday at the moment, otherwise we would have got him to write this article, but he has helpfully supplied a full list of all the states which have some kind of stake in each rail franchise operating in the UK. Thanks Jon.

It is worth noting that several operators have the same parent companies behind them.

Huge companies like Arriva UK Trains, Abellio and Govia run several operators.

For example, Govia runs Thameslink, Southern, Great Northern and Gatwick Express. The firm is a joint venture between Go-Ahead group and French company Keolis, which itself is 70 per cent owned by the French National Railways Corporation.

An Intercity 125 built by British Rail and used on routes including the Midlands and Great Western main lines (Creative Commons)

Meanwhile Arriva UK Trains is behind the operators, Chiltern, CrossCountry, London Overground, Grand Central, and Northern. In total it runs around a quarter of all British train operating companies, and is part of German firm Deutsche Bahn, in which the German state is the biggest shareholder.

Abellio is wholly owned by the Dutch national railways company Nederlandse Spoorwegen.

Private firm Virgin will no longer run the West Coast Mainline from December this year and the service will be run by a group consisting of the Italian state railway Trenitalia and private UK company First Group.

Here’s the full list:

c2c: Italian state

Chiltern: German state

Caledonian sleeper: PRIVATE

CrossCountry: German state

East Midlands: Dutch state

Eurostar: French state

Gatwick Express: French state

Grand Central: German state

Great Northern: French state

GWR: PRIVATE

Greater Anglia: Dutch state

Heathrow Express: PRIVATE

Hull Trains: PRIVATE

LNER: British state

London Northwestern Railway: Dutch state

London Overground: German state

London Underground: British state

Merseyrail: Dutch state

Northern: German state

Northern Ireland Railways: British state

Scotrail: Dutch state

South Western Railway: Hong Kong state

Southeastern: French state

Southern: French state

Stansted Express: Dutch state

TfL rail: Hong Kong state

Thameslink: French state

TransPennine Express: PRIVATE

Transport for Wales: French state

West Coast: Italian state

West Midlands Railway: Dutch state