Prime Minister Kevin Rudd has challenged Tony Abbott to a debate on asylum seeker policy and has accused the opposition leader of trying to "derail" his Papua New Guinea plan.
The government has struck a deal with Port Moresby that would see asylum seekers who arrive in Australia by boat sent to PNG for processing and resettled there if they're found to be refugees.
The policy is aimed at stopping the boats by ensuring no boat arrivals are resettled on Australian soil.
But Mr Abbott has described the policy as an unaccountable "cash splash" for PNG, that won't stop the boats.
Mr Rudd says Mr Abbott's stance is undermining the policy by muddying the message to the people smugglers.
"Partisan politics aimed to frankly derail the regional resettlement agreement is just an appalling approach to the responsibilities of the highest office of this land," Mr Rudd told reporters in Melbourne on Wednesday.
The prime minister challenged Mr Abbott to turn up to a debate on Melbourne radio station 3AW on the topic of asylum seekers.
"If you are too busy tomorrow morning Mr Abbott you pick the day - any day within the next week - and I'll come to Melbourne and join that debate," he said.
But Mr Abbott said if Mr Rudd wanted a debate he should either recall parliament or set the date for the election.
"Mr Rudd needs to understand whether he is governing or whether he is campaigning," Mr Abbott said.
Mr Rudd says the government will spell out how much the policy will cost in its pre-election economic statement, expected soon.
Asked about alleged sexual assaults at the Manus Island detention centre on PNG, Mr Rudd said it would be properly investigated.
Mr Abbott told reporters they were "very serious claims", and said the coalition had been warning the government for months of violence and abuse within onshore and offshore detention centres.
