(WASHINGTON) — Congress “must pass” new immigration laws, Homeland Security Secretary Alejandro Mayorkas said Sunday while defending the administration’s policies amid renewed scrutiny of the high amount of migration at the southern border.

“Because the border has been a challenge for decades, ultimately Congress must pass legislation to once and for all fix our broken immigration system,” Mayorkas told ABC This Week co-anchor Martha Raddatz.

Mayorkas’ defense comes after 53 migrants were found dead in a tractor-trailer in San Antonio, Texas, late last month, which Mayorkas called a “tragic result” of a “dangerous journey.” Four men have been charged in the deaths.

On This Week, Mayorkas said that the U.S. was working with regional allies in Central and South America beyond pushing for legislation, which remains a dim prospect in Congress.

“These are remarkable, distinct times,” Mayorkas said. In lieu of new laws, “we have a multi-faceted approach, not only to work with our partner countries but to bring law enforcement to bear to attack the smuggling organizations in an unprecedented way,” he said. “We are doing so very much.”

Raddatz pressed Mayorkas, noting that a legislative fix on immigration was unlikely given partisan gridlock on the issue — and, she said, the administration’s warning to migrants to not try to cross the border was either not being heard or not being heeded.

“Fifty-three people lost their lives in the most horrific of conditions,” Mayorkas said of the migrants who died in San Antonio. “We continue to tell people not to take the dangerous journey. We are enforcing our laws. And we are working with countries … including our close partner Mexico, but with Guatemala, Honduras, Panama, Costa Rica, Colombia, to really address the migration that is throughout the Western Hemisphere.”

Still, Raddatz cited a historic high in May for southern border crossings: 240,000.

“I think that we are doing a good job. We need to do better,” Mayorkas acknowledged. “We are focused on doing more, and we are doing it with our partners to the south.”

“You have Congressman Henry Cuellar saying that only about 30% of the Border Patrol are doing missions at checkpoints and the border because the other 70% are tied up at detention centers. How do you fix that?” Raddatz pressed.

“We are pressing this issue vigorously and aggressively to address the number of encounters that we are experiencing at the southern border,” Mayorkas responded.

He touted the administration’s recent win before the Supreme Court, which ruled last week that the White House can end the Trump-era “Remain in Mexico” policy that made migrants seeking asylum stay outside the U.S. during adjudication.

Mayorkas argued that policy “has endemic flaws and causes unjustifiable human tragedy.”

“We need to wait until the Supreme Court’s decision is actually communicated to the lower court, to the federal district court and the Northern District of Texas … So, we have to wait several weeks for that procedural step to be taken,” he said.

As for the migrant deaths in the tractor trailer in Texas, Mayorkas said he didn’t want to comment on the facts of the case as they were still emerging. He declined to say whether or not the vehicle had been “waved through” a checkpoint.

“The smuggling organizations are extraordinarily sophisticated. They are transnational criminal organizations,” he said.

Raddatz followed up, asking: “What good are these checkpoints if a truck like that gets through, full of migrants?”

Mayorkas said the “checkpoints are part of a multilayered approach.”

“In fiscal year 2022 alone we’ve stopped more than 400 vehicles and saved and rescued more than 10,000 migrants,” Mayorkas said. “But this is why we continue to communicate that the journey — the dangerous journey should not be taken. We are enforcing our laws and people lose their lives at the hands or exploitative smugglers.”

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