KfW IPEX-Bank has stumped up $186.3m for the 21,000-cbm vessels, it said in a statement today.
Some EUR 50.4m came via a complex structure covered by export credit insurance from Euler Hermes, the bank says.
Mike Abbott, chief financial officer of Petredec, said: "We are pleased to work with the German specialist financier as well as the German exporter who will contribute its technical expertise to the project.
“Both play an essential part in helping us expand our ship fleet, which is important to us."
Petredec has a fleet of 28 vessels, including 19 newbuildings, Clarksons Research Services says.
A dozen of those are under constructed at Hyundai Heavy Industries, while four are at Jiangnan Shipyard, two at Kyokuyo Shipyard and one at Sasaki Zosen.
It appears the loan relates to the quartet on order at Jiangnan but this could not be confirmed at the time of writing Thursday.