Kirby has agreed to pay a $4.9m civil penalty over the oil spill that resulted from a collision between a barge and a bulker in 2014.

US authorities said the settlement arises from allegations that the US barge owner is liable for the spill of 528 tonnes of heavy fuel oil into the Houston Ship Channel.

The penalty centres on the collision between barges pushed by the Kirby tug Miss Susan collided with Cleopatra Shipping’s 43,193-dwt Summer