By Agnes Constante

The federal government has said it is in the process of releasing some Vietnamese nationals in immigration detention who are excluded from deportation under an agreement between the U.S. and Vietnam, in what lawyers for the detained are calling a victory.

In a September court filing acquired by NBC News, an Immigration and Customs Enforcement (ICE) official wrote that the agency no longer believes that Vietnamese nationals who came to the U.S. before July 12, 1995 are “significantly likely to be removed to Vietnam in the reasonably foreseeable future.”

ICE’s stance shifted following an Aug. 6 meeting between senior officials and representatives of the Vietnam government, the document states. As a result, the agency wrote that it has proceeded to release pre-1995 Vietnamese who have been detained for more than 90 days and don't have a travel document.

Tung Nguyen, a Vietnamese national who was formerly incarcerated and came to the United States before 1995, welcomed the news.

“As an impacted individual, I’m happy that at this time I don’t have to live with uncertainty that ICE is going to come and detain me at any time,” he said.

An ICE spokesperson said the agency is unable to comment on ongoing litigation.

In 2008, the U.S. and Vietnam signed an agreement that excludes Vietnamese nationals who arrived in the U.S. before July 12, 1995 — the date the two countries reestablished diplomatic relations — from being subject to deportation. Many of those who arrived before that date were refugees of the Vietnam War.

In a February lawsuit by nonprofits Asian Americans Advancing Justice—Los Angeles, Asian Americans Advancing Justice—Atlanta, Asian Americans Advancing Justice—Asian Law Caucus, and law firm Reed Smith LLP, lawyers alleged that ICE was unlawfully detaining Vietnamese immigrants. The suit asserted that ICE had typically released pre-1995 Vietnamese immigrants with final orders of removal within 90 days of detention but began re-arresting those individuals in March 2017.

The lawsuit asserted that the U.S. had claimed that Vietnam was “willing to consider” repatriation of Vietnamese who arrived in the country before 1995.

Civil rights and immigration groups have previously said they believe seven pre-1995 Vietnamese nationals have been deported. ICE told NBC News in February that it does not track the year of arrival for those in immigration detention.

The September court filing noted that ICE intends to re-detain those released if the Vietnamese government indicates it intends to issue travel documents or if there is a significant likelihood an individual can be removed to a country other than Vietnam in the reasonably foreseeable future.

A federal judge in October certified the lawsuit as a class action that includes all Vietnamese immigrants who arrived earlier than the 1995 date and have been or may in the future be in ICE custody for more than 90 days after receiving a final removal order.

“We’re very much pleased by the court’s decision to certify the lawsuit as a class action and enable the thousands of Vietnamese refugees to participate in this case,” Christopher Lapinig, an attorney at Asian Americans Advancing Justice-Los Angeles who is working on the case, said.

He added that the court's certification means that any relief they're able to obtain will apply to an estimated 10,000 class members.

The groups will next request a court order stating that ICE is unable to deport pre-1995 Vietnamese and that Vietnamese nationals should not be detained for more than 90 days after receiving a removal order.

“ICE’s word is not enough because ICE has still admitted and conceded that removal to Vietnam is not reasonably foreseable,” Lapinig said. “But ICE has still not conceded that its practice of detaining pre-1995 Vietnamese immigrants has been unlawful at all, and that it still retains a right to detain our class members whenever it sees fit.”

Follow NBC Asian America on Facebook, Twitter, Instagram and Tumblr.