Just days before Australia's prime minister, Kevin Rudd, visits Papua New Guinea, a new twist has emerged in the battle to protect the Kokoda Track from a new copper mine.

Our PNG correspondent, Steve Marshall, says trekkers are not actually walking in the footsteps of diggers along the historic path after all.

Visiting historian, Soc Kienzle, whose father mapped the original war time route for the diggers, says the 600 metre stretch near the mine site is not part of the original war time track.

"They're moving along the main track and then they deviate off onto this side track, which is of no historical consequence for Australia or Papua New Guinea," he said.

Soc Kienzle says the original track will not be affected by the mine.

The Kokoda track runs for nearly 100 kilometres through the Owen Stanley Mountain Range in Papua New Guinea.

It is renowned as the location of the World War II battle between Japanese and Australian forces in 1942.

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