New information is surfacing about U.S. State Department guidance issued the day President Trump signed an executive order banning U.S. travel for individuals from seven predominately Muslim countries.

A department memo, dated Jan. 27 and acquired by WBUR, "provisionally revokes" all non-immigrant and immigrant visas of nationals from Iraq, Iran, Libya, Somalia, Sudan, Syria and Yemen as of last Friday.

The revocation, according to the memo, does not apply to diplomatic visas.

Kerry Doyle, a lawyer representing the petitioners in the Boston federal court filing that seeks to halt the enforcement of Trump's executive order, says the legal team was not aware that an official decision had been handed down by the State Department when they convened in Boston federal court late Saturday night and into Sunday morning.

Doyle says the new information explains why some people traveling with visas from those seven countries have not been able to board planes bound for the United States, following a temporary restraining order from Boston-based judges that said all lawful immigrants should be allowed entry.

"We had been under the impression that it was more a problem with Customs and Border Protection and the admission process and then coordinating with the airlines," Doyle said. "But we were unaware until that information was released that there was an official decision, or an official memo, from the State Department addressing the issue."

Green card holders from the seven countries are allowed entry on a case-by-case basis.

A State Department spokesperson responded:

At the request of the Department of Homeland Security, and in compliance with the President’s Executive Order, the Department of State provisionally revoked relevant visas as defined under the EO. Those visas are not valid for travel to the U.S. while the Executive Order is in place. The revocation has no impact on the legal status of those already in the United States.

The news of the revocation does not appear on the State Department website, and it's unclear whether visa holders from the seven countries listed in the executive order were notified that their visas had been revoked.

Mohsen Hosseini, a graduate electrical engineering student at UMass Amherst and a Iranian national, told WBUR in an email that he is unable to get back into the U.S. using his F-1 visa. Hosseini said he has completed one semester at UMass and traveled home over winter break to visit family.

Hosseini hadn't heard that visas had been revoked until WBUR informed him of the State Department memo on Wednesday. He replied that the entire ordeal is very frustrating.

"As you may know, getting [a] U.S. visa is a very hard process, and taking time," Hosseini wrote from Iran on Wednesday. "Personally, I experienced more than 3 month clearance for getting visa. I spend 2 years of my life for getting admission and visa from U.S. I wasted it."

Doyle, the local attorney, says the Boston-based legal team became aware of the State Department memo late Tuesday night just prior to filing an amended petition with federal court. The petition, in a footnote, says plaintiffs "reserve their right to further amend this Amended Petition once the purported action of the [State Department official] has been investigated."

She said the team is still digesting the implications of the State Department memo.

"And so now we have to strategize how we're going to respond to this new information," she said.

In a statement, Carol Rose, the executive director of the ACLU of Massachusetts, said the group is “deeply suspicious” of the State Department’s memo.

“We find it deeply troubling that -- just a few days from the first hearing in the nation on the executive order -- the government is claiming to have revoked the visas of thousands of people without whispering a word about it to them, to the courts evaluating the executive order, or to anyone else,” the statement read.

The ACLU of Massachusetts is part of the legal team representing the plaintiffs in Boston federal court. The attorneys will be in court Friday seeking to extend the stay of Trump's executive order.

The federal government has until noon Thursday to file an argument against the request for an extension of the stay on Trump's order.

With reporting by WBUR's Fred Thys

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