Amid a protracted stalemate in Congress over immigration, President Joe Biden has opened a new way to allow hundreds of thousands of new immigrants into the country, significantly expanding the use for people escaping war and political turmoil around the world.

The measures, introduced over the past year to offer refuge to people fleeing Ukraine, Haiti and Latin America, offer immigrants the opportunity to fly to the United States and quickly secure work authorization, provided they have a private sponsor to take responsibility for them. As of mid-April, some 300,000 Ukrainians had arrived in the U.S. under various programs — a number greater than all the people from around the world admitted through the official U.S. refugee program in the last five years.

By the end of 2023, about 360,000 Venezuelans, Cubans, Nicaraguans and Haitians are expected to gain admission through a similar means.