UN official slams Australia's boat policy

The United Nations' top human rights official believes Australia's policy of offshore processing of asylum seekers and turning back boats is leading to a chain of human rights violations.

The incoming UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein mentioned Australia in his maiden speech in Geneva.

He says they are concerned about the human rights situation of migrants around the world.

"I must emphasise that the detention of asylum seekers and migrants should only be applied as a last resort, in exceptional circumstances, for the shortest possible duration and according to procedural safeguards," he said in his speech.

"Australia's policy of offshore processing for asylum seekers arriving by sea, and its interception and turning back of vessels, is leading to a chain of human rights violations, including arbitrary detention and possible torture following return to home countries.

He thinks it could also lead to the resettlement of migrants in countries that are not adequately equipped.

The speech covers a range of other issues including Syria and Iraq.

Mr Al Hussein, who is from Jordan, replaces South African Navi Pillay as commissioner.