As uncertainty continues around President Donald Trump's controversial travel ban, those with green cards are flocking to immigration lawyers and nonprofits in the region to start the naturalization process.

Philippe Weisz, managing attorney at HIAS Pennsylvania, said his organization fielded 40 calls last month from immigrants wanting to become citizens. Last year, a typical month brought half that total.

As of last week, Weisz said HIAS had already gotten 14 calls about citizenship applications.

"We'll easily outpace the 40 calls we received last month," said Weisz.

Esperanza Immigration Legal Services and other nonprofits are experiencing the same uptick in application requests.

At Esperanza, the number of calls has tripled in the last two weeks since President Trump's executive order compared with the two weeks before it was announced.

"A lot of folks sort of questioned everything they had believed up to that point about their ability to freely travel, sort of have certain freedoms and rights as a green card holder," said executive director Mary Clark.

"We even have gotten calls from individuals who are naturalized citizens asking, 'Can my citizenship be taken away now?'"

Notably, the overwhelming majority of these application requests aren't coming from immigrants who hail from the seven, predominately Muslim countries — Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen — covered by the travel ban.

A number of calls are coming from immigrants from Central and South American countries, including Colombia and Venezuela.

Others are coming from Pakistan, Liberia and Burma, from people first came to the country as refugees.

Weisz, who said the nonprofit already had a waiting list more than a 100 strong, said the spike in application requests is straining HIAS resources.

"We are struggling to keep up with the demand," said Weisz. "To address that need, we've started to work with our pro-bono partners at both the large law firms in Philadelphia, as well as the solo practitioners who have really come out in the last couple of weeks.

This spring, Weisz and Clark's organization and others will begin hosting monthly citizenship clinics where permanent residents can work on the application process with a lawyer at different locations around the city.

Roughly a week after taking office, Trump signed an executive order barring residents of the seven countries from traveling to the U.S. for 90 days.

The order also blocked refugees from entering the country for 120 days.

On Thursday, judges on a federal appeals court unanimously refused to reinstate the ban, upholding a lower court ruling that suspended it, allowing ingress to the U.S.

An appeal to the U.S. Supreme Court doesn't appear to be out of the question.

After the court's ruling, President Trump tweeted, "SEE YOU IN COURT, THE SECURITY OUR NATION IS AT STAKE!"