Hours after Russia began a sweeping invasion of Ukraine, immigrant and refugee groups ramped up calls Thursday for the Biden administration to protect Ukrainians in the U.S. and prepare for a wave of refugees fleeing the embattled country.

Multiple organizations called for Temporary Protected Status or Deferred Enforced Departure to cover Ukrainians, designations that would allow them to remain in the U.S. without fear of deportation.

“The events presently transpiring in Ukraine warrant swift action and robust protections,” said Scott Boylan, leader of the Council on National Security and Immigration and former senior adviser at the Department of Homeland Security. Boylan called on the administration to fulfill its “obligation to provide humanitarian support for those caught in the crosshairs of invasion and political instability.”

Senate Foreign Relations Chairman Bob Menendez, D-N.J., also urged the Biden administration to offer Temporary Protected Status to Ukrainians.

“The war in Ukraine is exactly the type of crisis TPS was created for — to allow people to live and work in the United States when they are unable to return home safely,” he said in a statement.

Ukraine’s defense minister warned in December that a violent invasion could force between 3 million to 5 million Ukrainians to flee the country. Following the first military strikes against Ukrainian cities early Thursday morning, border crossings to neighboring Poland increased as Ukrainian citizens attempted to escape.

U.S. troops in Poland have begun preparing for an anticipated influx of evacuees, including American citizens living in Ukraine.

Refugee resettlement groups said the Biden administration should prepare more generally for broad movements of Ukrainian refugees, though it was not clear how many Ukrainians would seek out the U.S. over nearer European nations.

“The government and private sector should prepare for large-scale refugee flows and ensure those inside Ukraine can safely evacuate and restart their lives without fear of persecution,” said Kristie De Peña, vice president for policy at the think tank Niskanen Center.

De Peña also suggested a Special Student Relief designation for Ukraine, which would give Ukrainian students in the U.S. on F-1 visas more flexibility in their studies due to “emergent circumstances.”

Late Thursday, White House Press Secretary Jen Psaki said President Joe Biden was “certainly prepared” to accept Ukrainian refugees, but expects most will prefer to remain in Europe. She declined to predict whether the administration will issue humanitarian protections for Ukrainian immigrants already in the country.

In a statement earlier, DHS said it would “continue to closely monitor conditions in various countries across the globe” but had no announcements to share.

Despite raising the refugee admissions cap to 125,000 for fiscal 2022, which ends Sept. 30, the Biden administration had resettled just 4,362 refugees as of the end of January.

That low number reflects both a refugee resettlement infrastructure that had to be rebuilt after the Trump administration sought to dismantle it, as well as the draw of resettlement resources toward tens of thousands of Afghan evacuees.

“The refugee resettlement system is precisely how we protect vulnerable populations, whether they are from Afghanistan or Ukraine,” said Krish O’Mara Vignarajah, president of the resettlement group Lutheran Immigration and Refugee Service.

“The Biden administration’s increase of the refugee ceiling to 125,000 coupled with low refugee arrivals to date means there is ample room to welcome Ukrainians in search of safety.”