"Not another foot."

Those were the words Joe Biden used as a mantra throughout his 2020 presidential campaign regarding the construction of the U.S.-Mexico border wall. But on Thursday, the Biden administration approved a plan to complete a section of the border wall near Yuma, Arizona. 

The plan includes filling four major gaps in the wall that continue to allow the Yuma area to be one of the busiest corridors for illegal immigration crossings.

Department of Homeland Security Secretary Alejandro Mayorkas authorized the new plan, which was started by the Trump administration, in an effort to "deploy modern, effective border measures" and improve "safety and security along the Southwest Border," the agency said.

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A photo of a sunset behind a portion of the Yuma border wall

Migrant families from Brazil passing through a gap in the border wall after crossing from Mexico to Yuma, Arizona. (AP Photo/Eugene Garcia, File)

The project will be funded under Homeland Security’s 2021 budget, though it was initially planned to be funded by the Defense Department.

Yuma’s border sector remains an unsolved issue for the Biden administration as border patrol agents have already stopped migrants more than 160,000 times from January through June in the sector this year.

The figure is nearly quadruple the number of migrant stops from last year and the Yuma sector remains the busiest migrant sector in the state of Arizona. 

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Del Rio and Rio Grande Valley in South Texas were the only other sectors with more traffic along the entire U.S.-Mexico border.

The Yuma sector was notably busy under former President Trump, who had portions of the border wall constructed or reinforced. There was also a plaque installed along the Yuma border in 2020, affirming Trump’s role in securing the wall.

Biden’s decision to secure the border wall comes after Sen. Mark Kelly, D-AZ, has called on the president to secure the border. Republican lawmakers have made similar calls. 

The Biden administration’s quiet approval of the wall’s construction also comes after Biden often used it as a means of contrasting his policies with those of the Trump administration.

In the past, Biden was repeatedly critical of Trump, his border wall, and his immigration policies — which he referred to as "xenophobic" and "racist."

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In an op-ed published in the Miami Herald, Biden specifically wrote that the slogan "build the wall" was "divorced from reality" and a wall "won’t stop the flow of illegal narcotics or human trafficking, both of which come primarily through legal ports of entry."

"Nor will it stem the numbers of undocumented, most of whom over-stay legal visas," he added.

During an interview in August 2020, Biden told NPR's Lulu Garcia-Navarro: "There will not be another foot of wall constructed on my administration, No. 1." 

"I'm going to make sure that we have border protection, but it's going to be based on making sure that we use high-tech capacity to deal with it. And at the ports of entry — that's where all the bad stuff is happening," he added.

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Biden also ceased all new border wall construction after he took office and has told Congress to cancel funding for border wall construction.

He has since ramped up border security measures. Biden also continues to use billions of dollars Congress appropriated for the wall’s construction. He cannot legally refuse to do so — he is only permitted to pause border construction projects.

A distant photo of the Yuma sector border wall

A gap in the border wall between the U.S. and Mexico is seen from farmland in Yuma, Arizona on June 1, 2022. (PATRICK T. FALLON/AFP via Getty Images)

Republicans have repeatedly sued Biden for pausing the border wall construction. 

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"The Biden administration’s flat refusal to use funds that have already been set aside by Congress to build the border wall is not only illegal and unconstitutional. It’s also wrong," Texas Attorney General Ken Paxton said in a lawsuit filed October 2021.

In January, Biden announced a pause on constructing approximately 86 miles of a border wall along the Rio Grande citing an environmental review.

The Associated Press contributed to this report.