The ship was towed to safe waters after experiencing engine problems off off the Illawarra coast earlier this week.

It was rescued by tugs after fears it would crash into cliffs near Garie Beach.

The carrier is now berthed in Port Botany, NSW and will be detained after AMSA inspectors deemed the vessel's engines unsafe.

It'll be detained in the port until the identified problems are fixed and signed off as compliant.

"The vessel will be detained until AMSA inspectors are satisfied that the identified problems have been fixed," AMSA Executive Director, Operations, Michael Drake said.

"We have sent two inspectors and one specialist lead investigator on board to assess the vessel's mechanical and operational safety".

"While we can't say at this stage how long the vessel will be detained, it is unlikely to be longer than the several days it takes to fix the engines and ensure all mechanical components are compliant and operational".

A Port Authority of NSW pilot and four tugs supported the ship's entry into the harbour yesterday.

Meanwhile, the calmer weather conditions meant commercial shipping could resume in Port Kembla yesterday.