WASHINGTON – The Biden administration expands the pool of migrants allowed to enter the United States to file asylum applications in an effort to end President Donald J. Trump’s restrictive immigration policies.

The Department of Homeland Security said Tuesday that starting Wednesday it would consider migrants whose cases were dropped under a Trump-era program that gave border officials the power to send asylum seekers back to Mexico to wait for their cases to clear congested American immigration system. The change could affect tens of thousands of people.

President Biden had already ended the program officially known as the Migrant Protection Protocols. His government started accepting migrants enrolled in the program with pending asylum procedures this month.

In a statement, the ministry said the latest move was “part of our ongoing efforts to restore safe, orderly and humane processing to the south-western border”.

While many immigration and human rights activists welcomed the development, it will do little to ease pressure on the Biden administration to turn down hundreds of thousands of other migrants, many of whom are also seeking asylum and banned from entering the United States because of one of the states Health rule introduced during the coronavirus pandemic.

Democrats and human rights activists have long attacked the Trump program, which began in 2019 to prevent immigrants from crossing the southwestern border, despite having a legal right to seek asylum in the United States. Many of the asylum seekers enrolled in the program had completed their procedures because they could not appear for their trials in the United States while facing dangerous situations in Mexico.

“By keeping migrants in Mexico under dangerous conditions, the Trump administration ensured that many people could not appear for their hearings and that their demands would be rejected,” said MPs Bennie Thompson from Mississippi and Nanette Barragán from California, both Democrats, in a joint statement on Tuesday. Mr. Thompson is the chairman of the House Homeland Security Committee and Ms. Barragán is the chairman of the Border Security Subcommittee. “Giving these people the opportunity to be eligible for processing is the right thing to do.”

Rep. Michael Guest, Republican of Mississippi and a member of the House of Representatives Homeland Security Committee, said the decision was made in a hurry and without transparency.

“The division’s seemingly impulsive announcement lacked any explanation, reasoning or other evidence that the decision was made after careful deliberation and consultation, which are both reasonable and required by law,” wrote Mr. Guest in a letter to Alejandro N. Mayorkas , the State Secretary for Homeland Security.

The development could affect more than 34,000 asylum seekers in the United States, according to Syracuse University’s Transactional Records Access Clearinghouse, which collects immigration data.

Judy Rabinovitz, an attorney for the American Civil Liberties Union, said the process won’t be quick. Applicants would have to register and someone would have to tell them what to submit in order to reopen their cases. And there is no guarantee that an immigration judge would grant an application for reopening, let alone grant asylum.

In another major break with the Trump administration, the Justice Department overturned a Trump-era immigration ruling last week that had made it nearly impossible for people to seek asylum in the United States over credible fears of domestic violence or gang violence. The decision could affect hundreds of thousands of Central Americans fleeing gang extortion and recruitment, and women who have fled domestic violence in the United States since 2013.