Labour leadership contender Jeremy Corbyn has pledged to make Britain’s railways entirely state-owned and run by a citizens' corporation - dubbed the "People's Railway".
Yet many of Britain’s rail franchises are already owned and operated by state-owned companies – from Germany, the Netherlands and France.
Through a complex web of international subsidiaries, both state-owned and majority state-owned railway companies are operating millions of rail journeys across Britain.
And the profits are flowing back to their countries, funding public transport and spending across Europe.
Here are the top-performing foreign state-owned franchises on Britain’s rail network…
In 2012, Abellio - the Dutch state rail operator's international arm - made £3.64m on the Greater Anglia line. This flows back to the Netherlands.
London's Overground network is run as a joint venture between the German state rail operator Deutsche Bahn and private company MTR. In 2012, it made £7.54m profit, which is shared between the two.
This is a joint Serco-Abellio partnership. While Serco is a private company, Abellio is the Netherland's state rail operator's international arm. The Dutch state takes a share of profits - which totaled £10.77m in 2012.
Arriva is the German state rail company's international subsidiary. It wholly owns the CrossCountry franchise and made £12.9m profit in 2012.
Southern rail is a Kelios joint venture. Kelios is the French state's international rail subsidiary and it owns 35% of the franchise. This is equivalent to a £5.68m share of the £13.4m 2012 profit.
This line is run by Arriva - the international arm of Deutsche Bahn, the German train operator wholly owned by the German Federal government. Arriva Trains Wales made £13.6m profit in 2012.
The Southeastern line is 35% owned by Kelios, the French state rail operator's international subsidiary. In 2012, the line's £16m profit saw Kelios' share at £5.6m - flowing straight to France.
Northern is one of several Serco-Abellio joint ventures. While Serco is a private business, Abellio is wholly owned by Nederlandse Spoorwegan - the Dutch state's railway operator.
With a £33,033m profit in 2012, money flows from Northern coffers to fund Dutch public transport.
While First Group is listed on the London Stock Exchange, it’s TransPennine partner Kelios is majority owned by the French state railway operator. Kelios takes around 45% of the profits, or £22.55m in 2012.
All figures for financial year 2012. Source: Aslef (PDF).
But rail operators say that they're profits help keep Brits moving on the railway.
A spokesman for the Rail Delivery Group, which represents Network Rail and train operators, said: “Commercial train operators are delivering for passengers and taxpayers here in Britain. Compared to the late nineties, almost twice as many people are choosing to travel by train helping to increase fivefold the money paid back by operators to government for building a better railway.
"When rail franchising was introduced, Britain’s railway was running at a £2bn a year loss but faster passenger growth than any other railway in Europe means it now covers its day-to-day costs, so government can spend more on building the better network passengers and the economy need.”