A coalition government would keep open all options for dealing with asylum seeker boat arrivals including withdrawing Australia from the United Nations refugee convention.
But opposition immigration spokesman Scott Morrison said that would take a year to take effect, when action was needed at once.
Asked if a coalition government would take Australia out of the 1951 convention, he replied that he thought all options had to be kept open.
"If you were to withdraw from the convention it wouldn't take effect for a year. That's the process. What we think we have to do immediately is things that have an impact right now," he told ABC television.
Mr Morrison said boats could be successfully turned back and that was supported by a number of senior former military officers.
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"I am very confident about the navy's capacity to get the procedures in place as they did last time for this policy to be effective," he said.
Mr Morrison declined to reveal just how the policy would be applied.
"The smugglers will find out about that when they are confronted," he said.
"This is a war against people smuggling and you have got to approach it on that basis and we will not cease until it is done."
Mr Morrison said in every case on every occasion at every opportunity, a coalition government would put in place a deterrent.
"We will do that all the way back from our border, all the way up through the region, all the way up to the source countries as well. That is the resolve it takes to beat this."
Liberal MP Sussan Ley said it was important Australia did the right thing by the international community, but questioned the role of the convention in shaping domestic asylum seeker policy.
"Our policy should not be determined by that convention," she told Sky News on Thursday.
Prime Minister Kevin Rudd on Thursday indicated the government might call for the 60-year-old UN convention to be changed to reflect current movements of displaced people around the world.
Labor MP Stephen Jones agreed the convention should be looked at.
"But I don't think we can act unilaterally in this area," he told Sky News.
