Danish shipping giant A.P. Moeller-Maersk said Tuesday it had agreed to buy 11 "mega" container ships for $1.8 billion (1.6 billion euros) with the option to acquire another six from South Korea's Daewoo.
"These vessels will help us stay competitive in the Asia-Europe trade and will be key in our strategy to grow with the market," chief operating officer Soren Toft said in a statement.
The "mega" ships are 400 metres (1,300 feet) long and 58.6 metres wide and will each be capable of carrying more than 19,000 containers.
They will replace smaller, less efficient vessels and are due to be deployed between April 2017 and May 2018, the group said.
Maersk Line, the world's largest container transporter, has managed to outperform the market. The sector was hit by overcapacity after the financial crisis.
Last year it partnered with Swiss-Italian MSC under a deal similar to code-sharing agreements among airlines, allowing the companies to put cargo on each other's vessels.