US President Trump`s decision to suspend naturalization ceremonies is leaving residents across the country in an unusual position, now stuck in limbo after they were on the verge of gaining U.S. citizenship.

Critics say the pause is the Trump administration`s latest form of collective punishment for migrants, who have seen their hopes of citizenship dashed following the deadly shooting of a National Guard member in Washington, D.C.

On Thanksgiving, Trump said he would "permanently pause migration from all Third World Countries" in response to the shooting. The next week, U.S. Citizenship and Immigration Services (USCIS) suspended naturalization ceremonies for citizens of the 19 countries covered by the travel ban. It`s a list that`s since grown, as the president in December expanded the list to 39 countries.

In some cases, immigrants have already passed the citizenship test, only to be blocked from taking the oath that makes their naturalization official.

"People are just somewhat confused and concerned that, although they sort of went through the process, with the exception of the actual ceremony, that now at the eleventh hour, on the ninth inning they`re going to be disqualified and not allowed to be officially sworn in," Rep. Adriano Espaillat (D-N.Y.) said.

Espaillat, who is a naturalized citizen himself, said his office has been flooded by people dealing with the uncertainty.

"They`re in limbo, and I`m sure there`s a lot of stress. And they may feel they are Americans, but in actuality, they`re not, until they take that oath."

The U.S. typically naturalizes about 800,000 new citizens per year, the bulk of which are from Mexico, India and the Philippines.

"Naturalization candidates have been pulled from their scheduled citizenship ceremonies. I know this to be true because it happened to my constituents, who have reached out to my office," Sen. Dick Durbin (D-Ill.) said on the floor this week.

"They are rightfully upset that the administration has stopped them - individuals who are already approved for citizenship - from taking their oath of allegiance to this country."

The Trump administration has said the move is needed to thoroughly vet immigrants before they become U.S. citizens.

"USCIS has paused all adjudications for aliens from high-risk countries while USCIS works to ensure that all aliens from these countries are vetted and screened to the maximum degree possible. The pause will allow for a comprehensive examination of all pending benefit requests for aliens from the designated high-risk countries," a Department of Homeland Security spokesperson said in a statement.

"The safety of the American people always come first."

But immigration advocates say the claim simply doesn`t make sense, as many prospective citizens have been in the U.S. for years if not decades and have been vetted at every turn.

"They haven`t committed a crime, because otherwise they, you know, wouldn`t have been eligible for citizenship anyway. They have then submitted their application for naturalization, paid [the fee], found to be eligible because they took the citizenship test and the language test and passed everything," said Shev Dalal-Dheini, director of government relations at the American Immigration Lawyers Association.

"They were at the final, final stage of, you know - they are going to swear the oath of allegiance to the United States, and they are having the rug pulled out under them. So the rationale that the Trump administration is doing this because of security and vetting concerns doesn`t hold up. They have been vetted numerous times throughout various administrations, by multiple different government entities."

The Trump administration has been under pressure from Congress to resume the ceremonies.

Rep. Pramila Jayapal (D-Wash.) also led a letter asking USCIS for a breakdown of how many people have been affected by the pause, how applicants are being re-reviewed, and for a timeline for lifting the pause.

"It is this terrible feeling that I`m hearing from people across the country of, wait a second, I did everything the right way. I followed the process. I`ve done everything. I`ve been waiting all this time, you know, and you get, I mean, it is such a privilege and an honor to become a U.S. citizen. I remember what it felt like to me that day," said Jayapal, herself an immigrant to the U.S.

"I just had butterflies in my stomach, you know? First, I didn`t think I was going to be that affected, but I was in this room with people from all over - I`m getting goosebumps right now, just thinking about it - all over the world who had come from such different situations. I mean, people who had really escaped a lot of trauma, war, economic [issues], some were coming to join their families, and so they were there with their loved ones. And it was just this amazing, beautiful feeling, like, ‘I did it, I made it, I made it. I went through all of this and I made it.` And I remember just starting to cry. I was not expecting it at all, but I just started weeping, because it was just so beautiful and such a joyful moment."

Dalal-Dheini said many of those who are about to take the oath have already progressed though various immigration statuses, taking years to gain their green card and then eventually seek citizenship.

"It`s purely contradictory to our American values. We are a nation of immigrants. ... We are here because our forefathers are immigrants, and this is now saying, ‘You`re not welcome here,` even though that`s the foundation of this country," she said.

Even those not on the list of impacted countries are fearful to move forward.

There have been reports of residents from countries that are not on the travel ban list having their appointments canceled, and because other migrants have been arrested after immigration court hearings, some are fearful to make appearances.

"Now I`ve got people who are saying to me, ‘Should I go to my naturalization ceremony? What if they grab me in my naturalization ceremony?` It`s really unprecedented, and it`s attacking legal immigration. They`ve always said they want to attack undocumented immigrants, the so-called worst of the worst," Jayapal said.

"That`s not these people."