Vice President Kamala Harris is set to visit Douglas, Arizona, on Friday, marking her first trip to the U.S.-Mexico border since becoming the Democratic presidential nominee. Harris will deliver remarks to call for tougher border security measures as part of her efforts to address border issues, according to a senior campaign official. 

Harris plans to say that American sovereignty requires setting rules at the border and enforcing them, stressing that Border Patrol agents need more resources.

The vice president will make combating the flow of fentanyl a focal point of her remarks and refer to it as a “top priority” for her presidency. Harris will propose adding fentanyl detection machines to ports of entry along the border and will call on the Chinese government to crack down on companies that make the precursor chemicals utilized in the making of fentanyl. 

While Harris will stress the need for border security and address the lack of current resources, the vice president will also advocate for an immigration system that is “safe, orderly and humane” according to campaign officials granted anonymity to speak freely on the prepared remarks. 

As Harris is set to make her case on the border, the Biden administration will soon move to cement the asylum restrictions it enacted at the southern border over the summer, officials told CBS News. The planned amended proclamation would make it less likely for the asylum restrictions to be lifted in the near future, according to two U.S. officials who requested anonymity to discuss internal government plans. Officials have credited the stringent measure for a sharp drop in illegal border crossings in recent months.

Harris’ first border trip as the Democratic nominee comes as the vice president is looking to make gains on her opponent, former President Donald Trump, on border issues. According to a recent CBS News poll, 58% of likely voters consider the U.S.-Mexico border a major factor in deciding who they will vote for. The poll also found 53% of likely voters would support Trump starting a national program to find and deport all immigrants who are in the U.S. illegally. 

Trump and Republicans have long campaigned on the need for strong border security and have attempted to place blame on Harris for the influx of illegal crossings during the Biden administration. 

During a Thursday press conference in New York, Trump denounced Harris’ border visit, telling reporters “she should save her airfare.”

“She should go back to the White House and tell the president to close the border,” Trump said. “He can do it with the signing of just a signature and a piece of paper to the border patrol.”

Harris will argue, according to a senior campaign official, that Trump was responsible for scuttling a bipartisan border bill that would have enacted permanent asylum restrictions and authorized additional border agents and resources. Trump urged his allies in Congress to reject the bill earlier this year.

“The American people deserve a president who cares more about border security than playing political games,” Harris plans to say, according to excerpts previewed by CBS News.

While Harris has been pushing for Congress to pass the bill from the campaign trail, Trump on Thursday referred to the legislation as “atrocious.”

“It would allow people to come in here at levels that would be incredible and would allow them to get citizenship” Trump told reporters. “It was not a border bill. It was an amnesty bill.”

The measure that failed to garner enough support from Senate Republicans in the spring also included executive authority to turn away migrants during spikes in illegal immigration and would have expanded legal immigration levels. 

contributed to this report.