A ferry company that links Denmark with Sweden and Germany is reported to be up for sale.

Private equity firm 3i has hired the investment bank Rothschild to sell Scandlines, which was acquired a decade ago and could now be worth more than £600 million, according to The Sunday Times.

Scandlines carries about 15 million passengers, 3.2 million cars, 64,000 buses and millions of tons of freight every year on 12 ferries.

The sale will be complicated by plans for a new tunnel to link Denmark and Germany, duplicating one of the company’s main routes.

Both Stena Line and Scandlines have challenged EU support for the Fehmarnbelt fixed link, an 11-mile tunnel.

The sale is expected to lure interest from infrastructure funds, which have been acquiring transport assets perceived to have stable, long-term assets that match the liabilities of pension and insurance fund investors.