Prime Minister Malcolm Turnbull and Immigration Minister Peter Dutton have used a United Nations summit to encourage world leaders to look to Australia's strict border control policies as a way to give citizens confidence in accepting migrants.

Key points: UN meeting aims to find solution to global migrant crisis

UN meeting aims to find solution to global migrant crisis Turnbull and Dutton urge nations to follow Australia's lead

Turnbull and Dutton urge nations to follow Australia's lead Many groups have in the past criticised Australia's immigration detention policy

The pair defended Australia's controversial immigration policy at an unprecedented United Nations General Assembly meeting in New York, aimed at finding a better international solution to deal with 65.3 million people displaced around the globe.

Mr Turnbull outlined his view of the problem to the group, saying that the "unregulated movement of people globally is growing fast".

"We need measures to create order out of the resulting chaos," he said.

He urged the gathered world leaders to look to the Australian example for a solution.

"Addressing irregular migration through secure borders has been essential in creating the confidence that the government can manage migration in a way that mitigates risk and focuses humanitarian assistance on those who need it most," Mr Turnbull said.

Human Rights Groups and UN representatives have repeatedly criticised Australia's immigration detention policy, which is currently keeping more than 2,000 people in centres in Papua New Guinea, Nauru and Australia.

After Mr Turnbull's speech Save the Children issued a statement criticising the Prime Minister, saying he promoted an isolationist deterrence based model to asylum seeker policy that evidence has shown is expensive and takes a toll on those Australia should be aspiring to protect.

Oxfam and the St Vincent de Paul Society have also called on the Government to increase its humanitarian intake.

Vinnies' National Council CEO Dr John Falzon also criticised the Government's approach to boat turnbacks.

"The boats haven't stopped — they've just been turned away to other dangers," he said.

Speaking on behalf of the Prime Minister at another United Nations leaders' session, Mr Dutton also defended Australia's policies.

"Australia's recent history has seen extraordinary challenges to our sovereignty," he said.

"The way in which we've responded to these challenges has been critical to maintaining the confidence of Australians in our migration policy and practices.

"These policies and practices were not developed from a basis of fear, how could they be when one in four Australian residents born overseas and close to half of the population with at least one parent born elsewhere."

The comments coincide with news that another major service provider will not retender for a new contract at the Nauruan regional processing centre.

Connect Settlement Services, which provides welfare services to refugees and asylum seekers, has confirmed 100 staff will leave Nauru in December.

The company has declined to comment further on the decision, which comes less than a month after security service provider Wilson Security announced it would not seek a new contract after its current one ends in October 2017.

Turnbull promotes multicultural policy

Mr Turnbull used his speech to also defend the benefits of creating multicultural societies through migration.

"Diversity is an investment against marginalisation and extremism, it helps our community unite, rather than be divided," he said.

"At a time when global concern around immigration and border control is rising, the need to build community support for migration has never been clearer.

"Australia's experience bears this out."

Discussions on the migrant crisis will continue tomorrow in New York at a follow up summit convened by US President Barack Obama, where dozens of countries are expected to make pledges to significantly increase their humanitarian aid spending.