President Biden’s head of homeland security, Alejandro Mayorkas, said Sunday that the number of migrants trying to enter the United States illegally at the southern border has dropped by half since officials relaxed the pandemic-era protocols known as Title 42.

Appearing on ABC’s “This Week,” Mr. Mayorkas rejected critics of the administration’s immigration policies from both conservatives and liberals. Liberals have complained that Mr. Biden is reverting to President Trump’s strict policies and conservatives have complained that the current administration is too lenient with asylum-seekers.

“This is not an asylum ban,” Mr. Mayorkas said, addressing the concerns of liberals. “We have a humanitarian obligation as well as a matter of security to cut the ruthless smugglers out. That is a responsibility of government and we are doing that.”

Reporters on the ground at the border confirmed the declines with sources in the Customs and Border Protection department. Bill Melugin, a Fox News reporter in Texas who has been covering the crisis at the border for months, tweeted that illegal crossings in Texas have fallen “off a cliff” since the end of Title 42 Thursday. El Paso, he said, has seen a similar drop-off.

“After a peak of 3,300 on 5/8 in the [Rio Grande Valley] earlier this week — under 500 in RGV last 24 hours,” Mr. Melgun reported Sunday. “CBP contacts tell me they do not expect this lull to last. They expect numbers to crank back up again — but not to the record-setting levels we saw this week of 10,000+ per day.”

In his appearance on ABC, Mr. Mayorkas reiterated the administration’s assertion that new rules requiring that asylum-seekers be denied asylum in a third country such as Mexico or use the various legal pathways to apply are having the desired effect. “It’s not a ban on asylum, but they have a higher threshold of proof that they have to meet. That is a presumption of ineligibility that can be overcome,” he said.

Mr. Mayorkas criticized the decision late last week by a federal judge ordering the administration to stop releasing asylum-seekers without court dates when facilities at the border become overcrowded. He repeated earlier assertions saying the decision was “very harmful,” but said the administration would comply.

“When … our border patrol stations become overcrowded, it is a matter of the safety and security of people, including our own personnel, not just the vulnerable migrants, to be able to release them,” he said. “And this is something that administration after administration has done.”

The secretary of Homeland Security also defended the record of Vice President Harris, who early in Mr. Biden’s term was appointed “Border Tsar” to deal with the immigration crisis. He said Ms. Harris has been focused on the “root causes” of the crisis in the so-called Northern Triangle countries by leading investments of as much as $3 billion in Honduras, Guatemala and El Salvador and not the consequences of those root causes.

“That effort began in the Obama-Biden administration,” Mr. Mayorkas said. “It was terribly taken down during the Trump administration and Vice President Harris has led an extraordinary effort to address the root causes of why people flee their homes in the first instance — violence, poverty, corruption, authoritarian regimes, extreme weather events, persecution and the like.”

Ms. Harris, speaking at a Democratic fundraiser in Atlanta on Friday, failed to mention the immigration crisis at all. Asked afterward about GOP criticism of her appearance while the crisis escalated, Ms. Harris told WSB-TV that things at the border were going “rathern smoothly, given what the concerns were.
“The bottom line, however, is that this issue of immigration falls squarely within the responsibility of the United States Congress,” she added.