The final decision on an IPO is expected in the autumn, with Deutsche Bahn likely to sell a 45% stake in both. The company is seeking to reduce its €17.5bn debt and invest in modernising German railways.
He said the flotation exposed the “flakey and unstable nature of rail franchising”, with Deutsche Bahn allowed to win rail contracts and then hold a “corporate car-boot sale without any controls over who is getting a slice of the action”.
Rail staff terms and conditions are normally protected when franchises are awarded under TUPE laws, as are passenger services under franchise obligations.
An Arriva spokesman said: “Arriva has a strong track record of investment in the UK, investing £549m in the past five years and employing 28,000 people across the country.
“Deutsche Bahn is considering a third-party minority holding in Arriva which is intended to continue the successful development of Arriva and enable further investments in future growth.”