US says it will accept up to 100,000 Ukrainian refugees

President Joe Biden on Thursday will announce that the U.S. will accept 100,000 Ukrainian refugees, according to a senior administration official.

"To meet this commitment, we are considering the full range of legal pathways to the United States and that includes U.S. refugee admissions program, parole and immigrant and non-immigrant visas," the official told reporters.

The official also said the commitment to take in 100,000 Ukrainian refugees was not tied to any particular time frame.

The official reiterated that the administration still believed the majority of refugees would prefer to stay in neighboring countries or elsewhere in the European Union.

Eastern European cities and countries have become overwhelmed with refugees. A senior administration official told ABC News last week that the U.S. refugee program "is not an emergency response program, so our goal would be to provide humanitarian assistance to keep people safe where they are for now."

The process for refugees to stay in the U.S. is complex. Vetting it required as well as a referral from a United Nations agency. Secretary of State Antony Blinken said the administration is "looking at steps that we can take in the near term."

The White House did not announce specifics on how it will process these refugees. Administration officials said specifics will be announced "in the coming weeks."

The refugee resettlement process can also take years. In February, the U.S. admitted 427 Ukrainian refugees out of 2,133 refugees in total, according to Department of State data.

Since the beginning of the Russian invasion of Ukraine, more than 3.6 million refugees have fled the country, according to the U.N. Refugee Agency. The majority of the refugees have fled to nearby countries, with more than 2 million people crossing into Poland.

U.S. embassies and consulates in the region are processing emergency visa applications but are overwhelmed.

"We are not able to process the volume of the people who are thinking about that as an option," a senior administration official said last week.

According to U.S. law, immigrant visas only apply to immediate family -- meaning spouses, unmarried children under 21 and parents. Family not in that category can submit a petition to U.S. Citizenship and Immigration Services to approve their case.

Biden on Thursday will announce more than $1 billion in new funding for humanitarian assistance for those affected by Russia's war. "This funding will be additional to money that we have already provided and will provide food, shelter, clean water, medical supplies and other forms of assistance," a senior administration official told reporters. The U.S. will also provide $11 billion over the next five years to address food security threats and malnutrition across the world. This will be done through the Feed the Future initiative.

ABC News' Conor Finnegan contributed to this report.