Australia asylum

Australia sends asylum seekers who arrive by boat to centres in Nauru and Papua New Guinea's Manus Island.

Francois Crepeau, the UN special rapporteur on migrant human rights, has just finished an 18-day stint examining Australia's immigration laws.

He said in Canberra on Friday that conditions on Nauru were "cruel, inhuman and degrading".

"Australia would vehemently protest if its citizens were treated like this by other countries and especially if Australian children were treated like this," the Canadian lawyer said.

The lifetime ban on visas would apply even to those travelling as tourists, for business, or who married an Australian.

Prime Minister Malcolm Turnbull said the move would send "the strongest possible signal" to people-smugglers.

The proposed ban is to be put to parliament later this week.

Australia transports asylum seekers who arrive by boat to off-shore processing centres in Nauru and Papua New Guinea's Manus Island.