SYDNEY, Australia (CNN) -- The Australian government has decided to take part in the controversial U.S. missile shield system, a move likely to earn the displeasure of key trading partner China.

The conservative Howard government announced the move Thursday, after indicating in February this year that it would examine possible involvement in the project.

"We believe that taking part in the U.S. program will serve our strategic interest, help us defend Australia and allow us to make an important contribution to global and regional security," Foreign Minister Alexander Downer said.

Separately, local media in Japan said Japanese Prime Minister Junichiro Koizumi is planning to introduce a missile defense system to protect against the threat posed by North Korea.

Japan and the United States have been jointly researching a missile defense system since North Korea shocked Tokyo by test firing a missile that flew over Japan's main island in 1998.

"The reason Japan and Australia take a positive view of the missile defense system is because we think it's a common sense development to find a way to defeat ballistic missiles from rogue states should that situation arise," Downer told CNN.

Canberra has not yet determined the form of Australia's participation, with Downer saying it was too early to give specifics.

But he added there was a range of ways Australia would contribute, including areas such as science and technology, research and data exchange.

"In terms of bases, not only are we not being asked to provide bases but the details of the system haven't been fully developed yet," Downer told CNN. "The Americans, for example, may go for a ship-based system or a land-based system or a combination of the two."

However, Australia's Ministry of Defence on Thursday indicated some likely areas of co-operation.

These included:

• Joint work to help detect missiles at the point of launch
• Acquisition of ship and ground-based sensors
• Science and technology research, development, testing and evaluation.

Australia has been a steadfast ally of the Bush Administration on defense issues, including sending troops and equipment to the wars in Afghanistan and Iraq and backing the U.S. position in international forums such as the United Nations.

Arms race worries

Critics say the plan is unreliable, expensive and risks sparking a global arms race.

Support for the missile shield system -- also called Star Wars -- has been problematic, however, with China and close neighbor New Zealand expressing disquiet at the Australian stance.

Beijing, in particular, fears the U.S. system is designed to negate the effectiveness of China's somewhat modest nuclear arsenal and will be used to shield Taiwan and embolden pro-independence forces there.

China argues the system will undermine the global strategic balance, which could lead to a new arms race.

But Downer defended the system as a "common sense."

"I think it's very much a common sense precaution to find a way to defeat at least limited numbers of ballistic missiles from rogue states," the foreign minister told CNN.

"It's just a defense system and it could be used for example to defend coalition and allied troops in a combat situation or if there were to be a rogue state which was using ballistic missiles, it provides defense that otherwise doesn't exist."

Washington says the shield would protect against ballistic missiles that could soon be in the hands of so-called rogue states like North Korea.

It wants allies such as Britain and Australia involved in the project, particularly for the use of satellite tracking stations in their countries.

Australia already operates a ballistic missile early warning ground station jointly with the United States at Pine Gap in the remote Australian Outback.

Canberra's decision to participate in the missile defense program is also likely to draw more criticism from regional neighbors who have in the past accused Australia of acting as the United State's deputy sheriff.

But Downer rejected such claims.

"We are allies of the United States. We don't walk away from that. Of course we are nobody's deputy sheriff ... we are entirely independent. We make no apology for being close to the United States and supportive of many of the things the Americans advocate," he told CNN.

 

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Senator Hill said the US had invited Australia to join the program, along with unspecified other nations.

He said the government was looking at a long timeframe, but did not envisage a ground-based missile defence system on Australian territory.

But it would involve assisting with research and could involve incorporating a missile defence system into three planned air warfare destroyers for the Australian navy.

"We have given that careful consideration and we think that we can play a part, obviously a small part in terms of the massive overall program," he told reporters.

"We think that with the proliferation of long-range missiles and trends towards proliferation of mass destruction warheads, it is a sensible decision for Australia to take.

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"We believe that taking part in the U.S. program will serve our strategic interest, help us defend Australia and allow us to make an important contribution to global and regional security," Foreign Minister Alexander Downer said in a statement. Washington hopes to develop a shield against ballistic missiles, arguing "rogue states" like North Korea could soon have missiles to threaten the United States. It wants allies such as Britain and Australia involved in the project, particularly for the use of satellite-tracking stations in their countries.

Canada announced in May that it had entered formal talks with Washington  about joining the program. It was not immediately clear what other countries, if any, have committed to playing a role.

Downer told Parliament that "several countries in unstable regions" are developing ballistic missiles that in some cases would have the ability to carry weapons of mass destruction.

Critics said the technology for such shields - dubbed "Son of Star Wars" - is complex, unreliable and expensive but worse, the plans could spark a new arms race.

Australia has been one of Washington's staunchest allies over the last several years, pledging troops to the wars in Afghanistan and Iraq and stating its relationship with the United States is central to its long-term interests.

Downer said the nature of Australia's participation "will depend on many factors, including our own strategic defence needs, regional considerations, industry capabilities and financial considerations."

Australian Defence Minister Robert Hill said Canberra will likely help in research for the multibillion-dollar project and has no plans for a ground-based missile-defence system on Australian soil.

It may incorporate a missile-defence system into three planned air-warfare destroyers for the Australian navy.

"We have given that careful consideration and we think that we can play a part, obviously a small part in terms of the massive overall program," Hill said.

"We think that with the proliferation of long-range missiles and trends towards proliferation of mass-destruction warheads, it is a sensible decision for Australia to take."
 

Foreign Minister Alexander Downer told parliament in Canberra Thursday that joining the U.S. missile defense plan is in Australia's best strategic interests. Mr. Downer said it offers the best opportunity to protect Australia from ballistic missile proliferation. He also said it will allow Australia to contribute to global and regional security.

Defense experts say enlisting the support of allies like Australia is critical to the U.S. missile defense plan, because of the need to put satellite tracking stations in other nations.

Critics of the missile defense system say it is too expensive and too complex, and is likely to spawn a new global arms race. Australian officials argue the plan is purely defensive.

Australian Defense Minister Robert Hill said Australia will likely contribute to research for the project. Australia has been one of Washington's staunchest allies over the past several years, especially during the Bush administration's war on terrorism.