South Korea’s Polaris Shipping is to bolster its fleet with pair of Chinese-built newcastlemax newbuildings — ordered against long-term charters to mining giant Vale.

A source familiar with Polaris said the company had commissioned the two 218,000-dwt bulkers at Shanghai Waigaoqiao Shipbuilding (SWS).

“These two ships were ordered a few months ago but the newbuilding deal was never reported,” the source said.