US-based operator of dry bulkers Eagle Bulk Shipping has entered into an agreement to buy up to nine Ultramax dry bulk sister vessels from Greenship Bulk Trust.

The deal will see the company acquire a minimum of six Crown-63 Ultramaxes, with an additional 3 ships contingent upon final approval from Greenship's unit holders.

Eagle Bulk Shipping said that the contract has a value of US$153m, assuming all 9 ships are transacted.

Deliveries of the ships, which range in age from 2 to 5 years, is expected to start in April 2017.

"Eagle Bulk continues to execute on our fleet renewal and growth strategy, and today's announced acquisition affirms our ability to transact in a meaningful way," said Gary Vogel, Eagle Bulk's CEO.

"We view this as a milestone transaction, as it can increase our number of vessels by over 20% while meaningfully advancing the build-out of our owner-operator business model," added Vogel.