The group, including 300 marines and 100 navy personnel, will spend some 15 days drilling the loading and offloading of two ships carrying equipment and supplies for a Marine expeditionary brigade.

The marine brigade can fly in from another location on short notice, offload the ships and be ready to conduct military operations in a matter of days, the US military said in a statement.

It said the "equipment exchange" drill would involve two US Maritime Preposition ships, namely the MV Phillips and the SS Kopak, both based with Maritime Preposition Squadron-2.

The two ships are "strategically positioned to rapidly respond to any crisis in the Pacific region, including the Korean peninsula."

The US marines involved in the drill are being deployed from Okinawa, Japan.

A US marine officer told AFP the exercise was "not specifically tied" to the crisis over North Korea's nuclear drive.

"But it is important to note that we could rapidly respond to a crisis on the Korean peninsula," he said.

WAR.WIRE