The US State Department has approved the sale of the arms to Australia, but the deal still needs to be approved by congress.
The exchange is reported to be worth more than $US 895 million ($1.3 billion).
Defence Minister Richard Marles confirmed the deal was underway on Today this morning.
“We are working with the US on having more missile capability because it’s a really important part of what we need to be doing with our posture, which is to have a greater ability to project,” he said.
“That’s at the heart of what we’re doing with submarines, of course, but making sure we have longer range strike missiles is a really important capability for the country.
“It enables us to be able to reach out beyond our shores further and that’s ultimately how we are able to keep Australia safe.”
The US Defence Security Cooperation said the deal would include up to 200 Tomahawk Block V All Up Rounds and up to 20Tomahawk Block IV All Up Rounds.
These missiles have an operational range of more than 1600 kilometres – further than driving from Sydney to Adelaide – and has the capacity to “loiter” over a battlefield before choosing a target.
“This proposed sale will support the foreign policy and national security objectives of the United States,” the department said.
“Australia is one of our most important allies in the Western Pacific. The strategic location of this political and economic power contributes significantly to ensuring peace and economic stability in the region.
“It is vital to the U.S. national interest to assist our ally in developing and maintaining a strong and ready self-defense capability.”
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