Australian Prime Minister John Howard has denied that the Madrid bomb attacks automatically mean that something similar will happen in Australia.
There are fears that all supporters of the US-led war in Iraq are at risk
However, Mr Howard said it was vital for Australia to review its security procedures following the attacks.
He was speaking a day after warning remarks were made by Australia's Federal Police Chief, Mick Keelty.
Mr Keelty said if the attackers were Islamic extremists then all supporters of the Iraq war were at risk.
He said a similar event could occur in Australia, which like Spain backed the war and deployed about 2,000 troops there.
"It doesn't automatically follow that because something tragic ... like this has happened in Europe that it's going to happen in Australia," Mr Howard said.
"There is no direct link between what has occurred in Spain and Australia, no direct link at all."
"But I stress again that I cannot guarantee that there will be no terrorist
attack in Australia.," he added.
Thursday's bomb attacks killed 200 people and injured more than 1,500.
After initially blaming the Basque-separatist group Eta, the authorities have now shifted the focus of their investigation to Islamic extremists, possibly linked to al-Qaeda.
Mr Howard said it was well known that al-Qaeda viewed Australia as an enemy, but that this was the result of its peacekeeping efforts in East Timor, not its involvement in Iraq.
Australia got a real taste of terrorism in the Bali bomb attacks in 2002 when 202 people were killed, many of them young Australians. The attacks were blamed on Jemaah Islamiah, an Islamic group alleged to have links to al-Qaeda.
Mr Howard said that to ensure the country's security, Australia's National Counterterrorist Committee would try to learn from the Madrid attack, and weigh the risks to Australia's transport system.
The committee comprises government, police and security officials, as well as representatives from health agencies.