The Biden administration offered humanitarian relief to Ukrainians in the United States on Thursday, which could protect thousands from being deported to their war-torn homeland.

Ukrainians can remain in the country for up to 18 months under the federal program known as Temporary Protected Status. In order to be eligible for the protection, individuals would have to have been in the U.S. since at least Tuesday.

Also Read: US announces new sanctions on Russian oligarchs. Here is the list

The administration said the decision was made because of the Russian invasion into Ukraine, which marks the largest conventional military action in Europe since World War II. The invasion has caused a humanitarian crisis that has caused more than 1 million people to flee.

“Russia’s premeditated and unprovoked attack on Ukraine has resulted in an ongoing war, senseless violence” that has forced Ukrainians “to seek refuge in other countries,” Homeland Security Secretary Alejandro N. Mayorkas said.

Also Read: The truth behind Joe Biden’s forehead ‘bruise’: Explained

As many as 30,000 Ukrainians in the United States may benefit, according to the Migration Policy Institute, a nonpartisan think tank.

Pressure had been mounting on the Biden administration from lawmakers from both parties, including the Senate’s top Democrat, to grant the status to Ukrainians.

Sen. Majority Leader Chuck Schumer, D-New York, said: “Ukrainians around the world are experiencing the fear and uncertainty caused by President Putin’s premeditated and unprovoked invasion of their country.”

“I applaud President Biden for taking decisive action so that Ukrainians can stay safely in America,” he said in a statement.

New Jersey Democratic Sen. Bob Menendez, chairman of the Senate Foreign Relations Committee, said “after a week of Vladimir Putin’s illegal and ruthless war against the people of Ukraine,” it was the right thing to do.

He said he was heartened that “President Biden is once again making clear the United States will not relent in its support for the people of Ukraine in this dark moment in history.”

Refugee advocates also applauded the move. More than 177 organizations signed a letter sent to the administration last week requesting Ukrainians be offered the relief.

Krish O’Mara Vignarajah, president and CEO of Lutheran Immigration and Refugee Service, called it “a concrete show of solidarity with the Ukrainian people. Protecting Ukrainian families from deportation is the least we can do amid a Russian onslaught that has targeted civilians and civilian infrastructure.”

Citizens from a dozen countries are in the United States under the program designated for people fleeing ongoing armed conflict, environmental disasters, or extraordinary and temporary conditions.