Australia's highest court has ruled that the country cannot send asylum seekers to Malaysia as part of a new refugee swap deal.
The High Court reached a 5-2 majority decision on Wednesday to make permanent an injunction that has stood since August 8 and prevented Australia transferring 800 asylum seekers to Malaysia in return for Malaysia sending 4,000 registered refugees for resettlement.
The decision is a blow to the government that struck the deal with Malaysia to deter thousands of asylum seekers from Middle Eastern and Asian countries from attempting to reach Australia by boat.
The court said in a statement that Malaysia has not signed the UN Refugee Convention and the deal with Australia did not legally bind Malaysia to recognise the status of refugees under its domestic law.
It also said immigration minister Chris Bowen had no legal power to remove from Australia asylum seekers whose refugee claims have not yet been determined.
The case was brought to the court by 16 asylum seekers who were to become the first to be flown to Malaysia from the Australian territory of Christmas Island.
Malaysia has already begun sending registered refugees to Australia from among 93,000 now in the south-east Asian nation.