US President Donald Trump signs a revised executive order for a travel ban, leaving Iraq off the list of targeted countries, after his controversial first attempt was blocked in the courts.

US President Donald Trump has signed a new executive order banning travellers from six Muslim-majority countries after his controversial first attempt was blocked in the courts.

The new executive order will keep a 90-day ban on travel to the United States by citizens of Iran, Libya, Syria, Somalia, Sudan and Yemen, and comes into effect on March 16.

Iraq is no longer included in the ban because the Iraqi government has imposed new vetting procedures, such as heightened visa screening and data sharing, and because of its work with the United States in countering Islamic State militants.

Thousands of Iraqis have fought alongside US troops for years or worked as translators since the US-led invasion in 2003. Many have resettled in the United States following threats for working with US troops.

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After several weeks, Donald Trump has signed a new travel ban.

The new executive order also ensures that tens of thousands of legal permanent residents in the United States - or green card holders - from the listed countries would not now be affected by the travel ban.

More than two dozen lawsuits were filed in US courts against the original travel ban, which was signed on January 27, and the state of Washington succeeded in having it suspended by the 9th Circuit court of Appeals by arguing that it violated constitutional protections against religious discrimination.

.@POTUS has signed a new executive order that will keep the nation safe. Read it at https://t.co/XcBwwEJJHF pic.twitter.com/Yx2mikXl2A — Sean Spicer (@PressSec) March 6, 2017

POOL US President Donald Trump's new travel ban doesn't include Iraq, as the failed original ban did.

Trump publicly criticised judges who ruled against him and vowed to fight the case in the Supreme Court, but then decided to draw up a new order with changes aimed at making it easier to defend in the courts.

NEW BAN

The new executive order bans travellers from the six countries who did not obtain a visa before January 27, according to a fact sheet the administration sent to Congress.

RNZ Immigration law specialist Zach Norris says the new Trump travel ban will put New Zealanders under greater scrutiny if they have dual citizenship with one of the six countries on the banned list.

In addition, the nation's refugee program will be suspended for 120 days, and it will not accept more than 50,000 refugees in a year, down from the 110,000 accepted last year by the Obama administration.

The order represents an attempt by the Trump administration to tighten security requirements for travellers from nations that officials said represent a terrorism threat.

The new order provides other exceptions not contained in previous versions: for travellers from those countries who are legal permanent residents of the United States, dual nationals who use a passport from another country, those attending diplomatic missions, and those who have been granted asylum or refugee status.

"The United States has the world's most generous immigration system, yet it has been repeatedly exploited by terrorists and other malicious actors who seek to do us harm," the fact sheet stated.

The Department of Homeland Security was preparing to release the order publicly on Monday morning under an embargo. The Washington Post received the documents separately from an immigration lawyer who obtained them from a member of Congress.

The new order drew condemnation from immigrant rights advocates.

"The president has said he would ban Muslims, and this revised version - in these preliminary fact sheets - still does that, even if they have removed Iraq from the list," said Gregory Chen, director of advocacy for the American Immigration Lawyers Association.

"In its oral argument before the 9th Circuit, the government was unable to provide any evidence to the 9th Circuit that acts of terrorism had been committed by the nationals of seven countries initially designated. That was an embarrassment, but now weeks later, in these preliminary fact sheets, they still have not explained why people from these countries pose risk to America's national security."

MAJOR DISRUPTIONS

While the first order imposed restrictions immediately, the new directive would have an as-yet undefined implementation delay to limit the disruptions that created havoc for some travellers, the senior White House official told Reuters.

Refugees who are "in transit" and have already been approved would be able to travel to the United States.

Trump's original order barred travellers from the seven nations from entering for 90 days and all refugees for 120 days. Refugees from Syria were to be banned indefinitely, but under the new order they are not given separate treatment.

"This executive order has scrapped that division and the indefinite suspension, and has collapsed them into a single category of a 120-day suspension," the official said.

During the presidential election campaign last year, Trump called for a temporary ban on all Muslims entering the United States. He said his initial executive order issued just a week after he took office was needed to head off attacks by Islamist militants.

However, the White House official said the new order was based on national security considerations and had nothing to do with religion.

"It is substantially different from the first order yet it will do the same thing in this important way: It will protect the country and keep us safe," the official said. The administration would also reset the clock on the 90-day travel ban.

The official said US government agencies would determine whether Syria or other nations had made sufficient security improvements to be taken back into the refugee admissions program.

The new order launches a 90-day period for the Department of Homeland Security (DHS) to define a new series of requirements for countries to have full participation in US entry programs.

For countries that do not comply, the US State Department, the DHS and intelligence agencies can make recommendations on what, if any, restrictions should be imposed.

"It's not an all-or-nothing scenario," the official said.

The new order spells out detailed categories of people eligible to enter the United States, such as for business or medical travel, or people with family connections or who support the United States.

"There are a lot of explicit carve-outs for waivers and given on a case-by-case basis," the official said.

Many of Trump's supporters approved of the initial ban but critics said it was unjustified and discriminatory.

US technology firms who had employees affected by the executive order also complained, and some members of Trump's Cabinet urged him to remove Iraqis and green card holders from the list of those affected.

The White House was widely criticised for not working with the State Department, the Department of Justice, the Department of Homeland Security and allies in Congress in drawing up the initial ban.

The confusion that caused led to a weekend of chaos, legal wrangling and protests in cities and at major airports across the United States.

- Reuters and Washington Post

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