Australian Defence Minister Brendan Nelson has admitted that securing oil supplies is a key factor behind the presence of Australian troops in Iraq.
He said maintaining "resource security" in the Middle East was a priority.
But PM John Howard has played down the comments, saying it was "stretching it a bit" to conclude that Australia's Iraq involvement was motivated by oil.
The remarks are causing heated debate as the US-led Iraq coalition has avoided linking the war and oil.
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