THE Federal Government says it remains committed to having 500 asylum-seekers at the processing centre on Nauru by the end of the month.
Immigration Minister Chris Bowen on Monday signed the legislative instrument designating Nauru as a country for regional processing under the amended Migration Act.
Mr Bowen told Parliament that sending asylum-seekers to Nauru was in the "national interest, and he expected the first transfer of people would begin by the end of the week.
Just shy of 2000 people have arrived in Australia by boat since August 13, the day the government accepted in-principle the 22 recommendations of the Expert Panel on Asylum Seekers.
One boatload of people arrived on Sunday night when HMAS Glenelg and a merchant ship came to the rescue of a vessel carrying 82 asylum-seekers north of Christmas Island.
The latest arrivals came today, when two boats carrying a total of 139 asylum seekers were intercepted by Border Protection.
One boat was caught with 81 people on board, north of Christmas Island, while the second boat was carrying 58 people and was intercepted west-nor-west of the Cocos Islands.
Both groups of people will be transferred to Cocos and Christmas Islands for checks, and all those aboard could be eventually transferred to an offshore processing centre.
A motion authorising the designation of Nauru went before both houses of the Parliament on Monday afternoon and was expected to pass comfortably with support from the Coalition.
Mr Bowen did not reveal who would be among the first people transferred to Nauru, adding it would be a decision for the Immigration Department.
The Minister also revealed Transfield Services had won the contract, worth $24.5 million for the first six months, to provide catering, cleaning, security, transport and facilities on Nauru.
Transfield Services describes itself as a "global provider of operations, maintenance and construction services to the resources, energy, industrial, infrastructure, property and defence sectors".
Medical services will be provided by International Health and Medical Services, while the Salvation Army will provide support services in the areas of case management, community liaison and activities.
Mr Bowen said he had "full confidence" in Transfield Services, claiming it would provide "the best value for money".
"The department has engaged with a number of potential providers. Transfield Services ... have a wide range of experience, not just in engineering," Mr Bowen said.
The Nauru designation comes after the government struck an agreement with Papua New Guinea to establish a processing centre on Manus Island.
Australian Defence Force personnel and Immigration Department officials are expected to land on Manus Island within days to begin the process of establishing the centre.
Opposition immigration spokesman Scott Morrison, who with the arrival of each boat since August 13 had attacked the government for dragging its feet on getting Nauru up and running, accused the government of "making it up as it goes along".
The Greens, who are opposed to offshore processing, called for the establishment of independent panel of expert physicians to oversee the health and mental health of asylum seekers in indefinite offshore detention.
Senator Sarah Hanson-Young, who planned to introduce a bill in the Senate to establish the panel, said it would "add some humanity to an otherwise inhumane policy"