South Korean shipbuilder Hyundai Heavy Industries said Monday it had started construction on a Chinese order for the world's largest container ships.

China Shipping Container Lines (CSCL) awarded the contract for the five vessels -- each with a capacity of 18,400 TEU (20-foot equivalent unit) container boxes -- to Hyundai in May.

The size broke the previous record of the 18,000 TEU container ships another South Korean firm, Daewoo Shipbuilding and Marine, had built for Denmark's A.P. Moeller-Maersk.

Since the order was made, Hyundai said the vessels for CSCL had been further upgraded to a 19,000 TEU-capacity at the Chinese company's request.

Hyundai said in a statement that the first ship would be delivered in November.

Each ship will boast a 400 metre (yard) long deck, while standing 30.5 metres high and 58.6 metres wide.