US owner Tropical Shipping is expanding its fleet with an order for four new boxships in China.

Huangpu Wenchong is to build two 1,100-teu ships and two 300-teu units, brokers said.

Delivery is set for 2018, but no price has been revealed.

Tropical, which has two boxships and a fleet of ro-ros, is controlled by Saltchuk Resources of Seattle, also the parent of Sea Star Line and TOTE.