US shipbuilder Philly Shipyard has seen second quarter earnings reduced as costs rose.

The Oslo-listed company said net profit was $2.2m, compared to $5.4m in 2016.

Revenue jumped to $47.2m against $28.6m over the same period.

Contracts with Philly Tankers and Matson provide it with work through to the first quarter of 2019.

The order backlog stood at $576.9m at 30 June.