By Dominic Chopping

Maersk Line, the container shipping unit of Danish conglomerate A.P. Moller-Maersk A/S (MAERSK-B.KO), has ordered seven new container vessels for use in the Baltic and North Sea, it said Thursday.

The so-called "ice-class" vessels carry 3,600 20-foot equivalent containers and are designed to operate through sea ice. They have been ordered for Maersk's Seago Line unit and will replace several container vessels that are half the size or less of the new buildings.

It said the order is the first step in its previously announced five-year, $15 billion investment program, which will be spent on new vessel building, a retrofit program, containers and other equipment.

The vessels will be built by Cosco Shipyard Co., Ltd. in China with deliveries expected between April and November 2017. The order includes an option for two additional vessels to be declared within eight months.

The price of the order wasn't disclosed.

Write to Dominic Chopping at dominic.chopping@wsj.com; Twitter: @WSJNordics

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