Japanese sub heads to Australian exercise

A Japanese submarine and a pair of warships are heading to Australia to practise sub hunting off the east coast.

The Soryu-class JS Hakuryu is of the same type Japan is offering as a replacement for the navy's six Collins-class submarines.

The visit has been billed as Japan showcasing its submarine technology but a Defence source said on Friday it would have no impact on the ongoing competitive evaluation process to select a new sub design.

The Japanese vessels will work with Australian ships and aircraft in the latest round of the bilateral Nichi Gou Trident exercise series, designed to improve collaboration between the two navies.

Last year that was held off Japan, with Australian warships conducting controversial live-fire exercises with the Chinese navy on their way home.

Accompanying JS Hakuryu will be anti-submarine warfare destroyers JS Asayuki and JS Umigiri.

The exercise will be held in the east coast exercise area off Jervis Bay.

Japanese ships are scheduled to visit Sydney Harbour in mid-April, part way through the exercise.