Howard told a Commonwealth law conference there were similarities between the situation in Iraq and that in Australia.

"When you have strong ethnic and regional differences, it is only a federal system that can hold it together," he said.

Under its federal system, Australia has six semi-autonomous states responsible for issues like law and order, education and public transport, while the national government in Canberra is responsible for taxation, defence and foreign policy.

Howard said he endorsed an idea he had read in a newspaper article speculating that Iraq could borrow from the Australian experience and look at the development of a federal system of government.

"Perhaps there is some merit in that proposal as the people of Iraq think about their future," he told the conference in Melbourne.

"When you reflect upon the strong Kurdish component in the north, the Shia preponderance in the south and the Sunni preponderance in the middle, perhaps there is some merit in a federal experiment in Iraq."

But Howard said it was not the desire of Australia, Britain or the United States to impose an alien solution on another country and it would be up to the Iraqi people to develop their own system of government.

The conservative Australian leader, whose audience included barrister Cherie Booth, wife of Britain's Labour Prime Minister Tony Blair, expressed his "profound respect and admiration" for Blair.

Booth reciprocated by passing on her husband's gratitude for Australia's "magnificent" contribution to the war.

Like Blair, Howard has faced often bitter criticism at home over his government's decision to join the US "coalition of the willing" in Iraq.

But both have seen a dramatic turnaround in public attitudes, with polls in Australia now routinely showing majority support for the war when initially they indicated overwhelming public opposition.

Howard earlier defended the war, arguing it was the only way to remove Saddam Hussein and that its successful conclusion would make the world safer from terrorism.

"The whole idea that you could bring about regime change, the whole idea that you could provide the hope and the opportunity for the people of Iraq that has been provided without taking the action that was taken, is ludicrous," he said.

He described the military operation in Iraq as "quite brilliant" and advised journalists critical of the war to remain "silent for their own credibility."

"If what the coalition did was wrong, according to these people, how else do they think Saddam Hussein would have been removed -- by somebody issuing a press statement?" he said.

Howard rejected the view that Australia's involvement in the war had made it a greater terrorist target.

"My own view is that in the medium to longer term what has happened has made the world a little safer from terrorism," he said.

"What has been signalled to terrorists as a result of this action is a determination of the civilised world to go after them and to defend themselves against potential terrorist attacks."

SPACE.WIRE