Prime Minister Malcolm Turnbull insists it is "not his job" to comment on US President Donald Trump's decision to curb immigration, despite strong criticism from the United Kingdom and Germany.

Key points: Turnbull refuses to comment on Trump's immigration ban

Turnbull refuses to comment on Trump's immigration ban Morrison compares Trump's actions to his own after 2013 election

Morrison compares Trump's actions to his own after 2013 election Australians who have visited Iran, Iraq, Sudan or Syria since 2011 are 'red flagged'

Australians who have visited Iran, Iraq, Sudan or Syria since 2011 are 'red flagged' Labor calls for clarity on how the ban will impact Australians

More than 110,000 Australian residents were born in one of the seven countries on Mr Trump's temporary immigration blacklist, which bans travel to the US for 90 days.

But thousands more would-be travellers to America may be caught out by another change in US immigration law, which "red flags" Australians who have travelled to Iran, Iraq, Syria or Sudan since March 2011.

Despite these concerns, Mr Turnbull has refused to comment on Mr Trump's executive order, saying instead Australia's immigration and border security policies were "the envy of the world".

"It is not my job as Prime Minister of Australia to run a commentary on the domestic policies of other countries," he said.

"We've got very strong systems — that is a fact. We're proud of those and we'll maintain them and where we can, we will enhance them."

Foreign Minister Julie Bishop has told diplomats in Washington DC to lobby the Donald Trump administration and ensure his latest executive order does not apply to Australian dual nationals.

The Canadian Government claims its citizens are exempt from the new visa restrictions while the UK Government asserts the temporary ban does not apply to full British nationals.

Mr Turnbull said the Department of Foreign Affairs and Trade (DFAT) had not received requests for consular assistance from Australians unable to enter the US.

Mr Trump's executive order also suspends all refugee admissions for 120 days with case-by-case exemptions and suspends entry of Syrian refugees indefinitely.

The order was partially stayed by an emergency court ruling, in response to a case filed by the ACLU on behalf of Iraqi men Hameed Khalid Darweesh, who had been an interpreter for the US military, and Haider Sameer Abdulkhaleq Alshawi.

Treasurer Scott Morrison compared Mr Trump's executive orders to his actions as immigration minister shortly after the 2013 federal election.

"The rest of the world is catching up to us and how the US wants to handle that is a matter for them," he told Sydney radio station 2GB.

"They have had an election, and the President is implementing what he said he would do.

"I remember when we came [into office] in 2013 and I was implementing our border protection policy, people threw their hands up and I said, 'look, I'm doing what I said I'd do and the way I said I'd do it'.

World leaders condemn ban

Elsewhere, British Prime Minister Theresa May ordered two of her most senior ministers, Foreign Secretary Boris Johnson and Home Secretary Amber Rudd, to call their US counterparts in protest.

Britons affected by the ban include decorated Olympian Sir Mo Farah, who was born in Somalia.

German Chancellor Angela Merkel also spoke out against the ban, saying the fight against terrorism was no excuse for banning refugees.

Canadian Prime Minister Justin Trudeau said his country welcomed those fleeing war and persecution, "regardless of your faith".

Among the first leaders to voice criticism was French President Francois Hollande, who said: "When [Mr Trump] rejects the arrival of refugees, while Europe has done its duty, we should respond to him."

Italian Prime Minister Paolo Gentiloni said "open society, plural identity, no discrimination" were the "pillars of Europe", while the Danish, Swedish and Norwegian Governments also registered their opposition.

Australians face more travel barriers

While Mr Trump's executive order is drawing condemnation internationally, it is not the only barrier to entry for Australians.

A US law called the Visa Waiver Program Improvement and Terrorist Travel Prevention Act 2015 has already caught out thousands of would-be travellers to America.

Since April 1, 2016 the law has banned anyone from entering the US on its visa waiver scheme if they had travelled to Iran, Iraq, Sudan or Syria since March 2011.

Many Australians "red flagged" because of previous travel have since been turned away at airport check-in desks, unaware their travel history is now a barrier for entry.

This has included Australians planning to transit through a US airport to a third country.

Those who were blocked could apply for a traditional non-immigrant visa from the Department of Homeland Security, but needed to do so in advance of their travel.

Because of the large number of Australian Defence Force members who worked in Iraq during the period, an exemption was granted to allow them to continue entering under America's electronic visa scheme.

The Department of Foreign Affairs and Trade has since updated its travel advice for Australians travelling to the US warning of changes in American policy.

"Any of these Australians who have previously been issued an Electronic System for Travel Authorisation [ESTA] are likely to have the ESTA revoked," the statement said.

Labor says Government 'missing in action'

Opposition Leader Bill Shorten said the temporary ban was "appalling and ought to be ended as soon as possible".

"I urge Malcolm Turnbull to reconsider what our nation’s position ought to be and rethink what he should be saying on our behalf," he said.

Labor's Tanya Plibersek said the Government was "missing in action" and needed to provide Australian travellers with clarity.

"I think it's absolutely vital now that the Australian Government seek clarification about how this will affect Australian citizens," she said.

"We've seen UK Prime Minister Theresa May make it clear that she does not support this travel ban.

"I think it would be very important for the Australian Government to make a clear statement about its view on this discriminatory travel ban."

Ms May has ordered two of her most senior ministers, Foreign Secretary Boris Johnson and Home Secretary Amber Rudd, to call their US counterparts in protest.

German Chancellor Angela Merkel, who has been criticised by Mr Trump for her immigration policies, has criticised the ban, saying the fight against terrorism was no excuse for banning refugees.

Labor's foreign policy spokeswoman Penny Wong has written to Ms Bishop calling for greater clarity on how the ban will impact Australian travellers.

"As you are no doubt aware, this is causing a great deal of concern to members of the community," she said.

Labor's Anne Aly, who is also a legal expert on countering radicalism, said the order would be "completely ineffective" and was not designed with security in mind.

"If anything, it is counter-productive," she said.