Private equity groups 3i and Allianz Capital Partners are considering the sale of Scandlines, hoping for up to 1.4 billion euros ($1.8 billion) for a ferry group that carries 12 million passengers around the Baltic, people familiar with the situation said.

London-listed 3i and the private equity arm of German insurer Allianz, which each own 50 percent of the company, have invited banks to pitch for the role of selling Scandlines next year, five people said.

The plan comes as pressure increases on private equity groups to sell some of their largest and most mature companies after a slow year for deals in 2012.

3i and Allianz Capital Partners bought Scandlines at the peak of the buyouts boom in 2007, paying 1.5 billions euros for the largest ferry group in the southern Baltic, alongside minority investor Deutsche Seerederei GMBH.

3i and Allianz then bought out their partner in 2010.

Scandlines concentrates on the major passenger routes between Germany, Denmark and Sweden, carrying some 12 million passengers, 2.7 million cars and 831,000 trucks last year.

The company had revenues of 611 million euros in 2011, a rise of 8 percent, and total earnings before interest, tax, depreciation and amortisation of 167 million euros, according to its annual report.

The business could attract interest from rival private equity houses, such as EQT or Triton, but could struggle to reach the 1.4-billion-euro asking price, despite recent improvements in performance, two of the people said.

Swedish ferries group Stena Line bought five longer-distance freight ferry routes from Scandlines earlier this year for an undisclosed amount but is unlikely to be interested in the whole business, the people added.

"The longer term picture is very uncertain. The biggest concern is the planned tunnel between Denmark and Germany," one of the people said.

An undersea road and rail tunnel between Germany and Denmark across the Fehmarn Belt has been proposed and is being planned for 2020. If it goes ahead, it would hit passenger numbers on one of Scandlines busiest routes.

The company has also been buffeted by high oil prices, aggressive price competition from toll bridges on some of its routes and faces a threat to its onboard retail sales as the harmonisation of taxes between Germany, Denmark and Sweden reduces the incentive for passengers to buy wines and spirits.

Scandlines is one of the largest companies under 3i ownership and increasingly out of place as the group scales back its investment plans to focus on smaller companies, amid a painful restructuring of the private equity group.

Allianz has its share of woes too, losing control of printing press maker Manroland last year to lenders. The group is pulling out of fiercely competitive private equity investing to focus on infrastructure deals.

3i and Allianz Capital Partners declined to comment.

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