Homeland Security Secretary John Kelly affirmed Sunday night that President Donald Trumps executive order banning refugees and travelers from several majority-Muslim countries would not apply to permanent residents, a major source of confusion in implementing the policy.

In applying the provisions of the presidents executive order, I hereby deem the entry of lawful permanent residents to be in the national interest, Kelly said in a statement. Accordingly, absent the receipt of significant derogatory information indicating a serious threat to public safety and welfare, lawful permanent resident status will be a dispositive factor in our case-by-case determinations.

Issued Friday, Trumps executive order, which restricts refugees in general and travelers from seven majority-Muslim countries, wreaked havoc on immigration procedures over the weekend .

The hastily written order contained vague language and no specific guidance on whether it applied to certain groups. Permanent residents, also known as green card holders, were being admitted on a case-by-case basis.

Immigration attorneys and advocates told HuffPost that it amounted to chaos.

They drop this order at 4:30 p.m. on a Friday, said immigration attorney David Leopold . Everyones leaving the office. Lawyers are gone. Reporters are leaving for the weekend. But planes are coming into the country. Nobody had any notice whatsoever. Nobody knew this was going to apply to permanent residents.

Even Trumps chief of staff, Reince Priebus, on Sunday contradicted himself in stating whether the ban applied to permanent residents. He first told NBCs Meet the Press that as far as green card holders moving forward, it doesnt affect them. But minutes later, he said, Of course it does.

The Department of Homeland Security (DHS) issued another statement on Sunday affirming that we are and will remain in compliance with judicial orders. We are and will continue to enforce President Trumps executive order humanely and with professionalism.

But Stephen Legomsky, the former chief counsel to U.S. Citizenship and Immigration Services, told HuffPost in an email that how the executive order affects permanent residents is still not entirely clear, and that in enforcing the policy, officials will exhibit different degrees of aggressiveness.

According to a DHS fact sheet on enforcing the executive order , released a full 48 hours after Trump signed it on Friday, lawful permanent residents can expect swift entry and will be allowed to fly back to the U.S., but they are still subject to national security checks.

In a letter Sunday night, House Democratic leaders implored Kelly to address the widespread chaos and confusion caused by the order, and requested an emergency meeting with him this week to discuss it.

Despite the confusion and mass protests against the ban, a Trump administration official on Sunday boasted that it was a massive success story. On Saturday, Trump claimed it was working very nicely.

Roque Planas contributed reporting.

This is a developing story and has been updated.

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