This was not accepted by the Howard Government, which contended that international law obliged Australia to provide temporary protection only and not necessarily permanent settlement. The Australian government claims that in the excised areas Australia has no obligation to grant asylum seekers a visa to settle permanently in Australia (as opposed to temporary protection). The main objective of excising areas from the Australian migration zone is to limit access of unauthorised arrivals to review by Australian courts. Asylum seekers who land in an excised area may only apply for refugee status with the UNHCR. The Acts also included the powers to move unauthorised arrivals to another country where their claim for protection could be considered. Under this authority, thousands of asylum seekers have been moved to off-shore immigration detention facilities on Christmas Island, Nauru, and Manus Island. In subsequent years the government excised other islands, sometimes attempting to do so retroactively, after asylum seekers had already landed. However, the Rudd Government abolished the temporary protection visa scheme in 2008. The practice of diverting boat-borne arrivals to Christmas Island remained, effectively disallowing judicial review. On 16 May 2013, the Australian Parliament passed an Act to excise the entire Australian mainland from the migration zone. At times there has been confusion over the effect on Australia's sovereignty over the excised area. Various constitution authorities have voiced the opinion that excising territory from the migration zone does not affect Australia's sovereignty. The "excision" of areas from the migration zone has no impact on the rights of Australian citizens and permanent residents to travel to and remain in that area, and no documentation is required to travel between these areas and the rest of Australia. Nor is there any impact on the rights of those non-citizens who arrive in these territories with valid visas. Norfolk Island, an Australian external territory, was brought within the Australian migration zone on 1 July 2016. From that date, anyone living on Norfolk Island needed to be an Australian citizen or hold a visa under the Australian "Migration Act 1958", and all island legislation on the matter ceased to apply. The Department of Immigration and Border Protection became responsible for administering the system and non-citizen permit holders (except those holding visitor permits) or permanent residents of Norfolk Island were given comparable Australian visa categories. However, a new temporary visa, called Provisional Resident Return visa (subclass 159) was created for those persons who held a work permit for Norfolk Island, who were then only entitled to work on Norfolk Island, and not the rest of Australia.