Homeland Security Secretary Alejandro Mayorkas on Wednesday defended the right to claim asylum and sharply rebuked “deterrence” policies that the previous administration used to discourage migration to the southwest border, while insisting the U.S. border remains “closed.”

In particular, Mayorkas took aim at the Trump administration’s use of its zero-tolerance policy to separate migrant families at the border.

“Sometimes the tools of deterrence defy values and principles for which we all stand. And one of those tools of deterrence that the Trump administration employed was deplorable and absolutely unacceptable,” he told members of the House Homeland Security Committee.

In his testimony, his first as secretary, Mayorkas often found himself fielding criticism from congressional Republicans on his response to increased border crossings and White House messaging to migrants considering the journey to the United States.

“Deterrence does work,” Rep. Michael McCaul, R-Texas, told Mayorkas. He also took issue with previous remarks made by the secretary that the U.S. is not telling migrants, “Don’t come,” but rather, “Don’t come now.”

Mayorkas responded to McCaul and other congressional Republicans by arguing against their claims of a “crisis” at the U.S.-Mexico border.

“If we want to speak of language, then let me speak of language,” he said. “I will share with you how I define a crisis. A crisis is when a nation is willing to rip a 9-year-old child out of the hands of his or her parent and separate that family to deter future migration.”

Later, Mayorkas said he did not recall his past statement, made during a March 1 press briefing at the White House, that migrants shouldn’t come to the country “now.”

“I don’t recall, but I think the message is in fact not to come to the border, not to take the perilous journey. The border is not open,” he said.

His comments echoed those of President Joe Biden in an interview with ABC News the previous night, when he told migrants, “Don’t come over.”

Biden said, “Don’t leave your town or city or community. We’re going to make sure we have facilities in those cities and towns run by DHS.”

While maintaining the border is closed, Mayorkas also said that migrants have the legal right to seek humanitarian protection in the U.S. under asylum laws, after Rep. Dan Bishop, R-N.C, pressed him on that issue.

“A claim of asylum is a claim that is recognized by law in the United States of America. And an individual who makes a claim of asylum is not breaking the law by doing so,” Mayorkas told lawmakers. “As a law enforcement officer, I enforce the laws of accountability as well as the humanitarian laws that Congress passed.”

He also stressed the need to send foreign aid to Central America to address the root causes of migration.

“We can talk about the pull factors, which certainly a number of us have referenced this morning. But we have to understand that the push factors are so extraordinary,” he said. “Imagine loving parents willing to allow their young child under the age of 18 to leave home, traverse Mexico alone, to reach our southern border. That speaks of the level of desperation.”

The day before the hearing, Mayorkas said in a public statement that the U.S. is on track to encounter more migrants this year than it has in 20 years.

[Mayorkas defends border response, expects 20-year high]

Homeland Security Chairman Bennie Thompson, D-Miss., in his opening remarks asked Mayorkas to discuss “how the department is responding” to the situation at the border and to explain “his vision for the way forward on homeland security.”

Border agents recorded more than 100,000 crossings in February, including more than 9,000 migrant children arriving without their parents, according to data published by U.S. Customs and Border Protection. Some of those encounters represent migrants who attempted to cross the border more than once.

These figures are significantly higher than the number of migrants encountered this time last year but still remain below those seen in the spring of 2019.

According to Mayorkas, most of those migrants are single adults who are rapidly “expelled,” or turned back, under a public health directive. The U.S. has also continued to expel migrant families when Mexico has capacity, although unaccompanied children have been exempted from the order.

At Wednesday’s hearing, Republicans repeatedly drilled into DHS procedures to test those migrants who are exempted from the health directive for COVID-19 before being released into the U.S.

Mayorkas said DHS is working with local officials and community-based organizations to test migrants and quarantine them if necessary. Those organizations can then be reimbursed for those services by the Federal Emergency Management Agency, he said.

The responses failed to satisfy several Republicans, including Rep. Clay Higgins, R-La., who told Mayorkas his testimony was “nauseating.” He accused the secretary of dodging “hard questions” and instead delivering a “prepared narrative.”

After additional questioning on COVID-19 testing at the border by Rep. Andrew Clyde, R-Ga., Mayorkas conceded that migrants previously had been released into the U.S. without first being tested, but the department has since “addressed that situation.”

“We are doing the best we can to ensure that the policy is executed 100 percent of the time. That I can say,” Mayorkas said.

Some committee Democrats questioned their Republican colleagues’ concern for the spread of coronavirus in border towns, given their past opposition to local COVID-19 restrictions and mask mandates.

“I appreciate the challenge you face on the border. What I don’t appreciate, though, is the feigned concern of my colleagues about these being superspreader events. These are colleagues of mine who spent the last year going to superspreader events, a number of them at the White House,” said Rep. Eric Swalwell, D-Calif.

“I just don’t believe that they have a genuine concern of the health of the people at the border,” he added.