"The international community's success in responding to new proliferation threats depends on governments' willingness to work together to take practical measures," Howard wrote in The Wall Street Journal.

He expressed regret that a UN summit that took place in New York last week failed to outline a comprehensive counterproliferation strategy in its final document.

But Howard underscored the importance of the Proliferation Security Initiative (PSI) that was launched by US President George W. Bush in 2003 and that calls for disrupting and deterring WMD and missile-related trade.

The Australian leader said that since the United Nation had failed to act, initiatives like the PSI are playing "an increasingly important role in the fight against proliferation."

"The resolve of participating countries in PSI sends a clear signal to proliferators that their activities will not only not be tolerated -- but that they will be stopped," he stated.