Hapag-Lloyd chief executive Rolf Habben Jansen has raised concerns about the growing use of dry bulk vessels to carry containers.
He described bulkers as "inefficient" and likely to worsen problems at congested container ports, while making little difference to the total volume of containers moved.
Speaking at a press briefing on Thursday, Habben Jansen said carriers are deploying "every ship they can find" as extra-loaders.
