By James Oliphant

Florida Governor Ron DeSantis defended flying planeloads of migrants across the country during a trip to the U.S. southern border on Wednesday, as he looks to make hardline immigration policies a central tenet of his 2024 presidential bid.

The Republican candidate's stop in Arizona came a day after the state of Florida acknowledged it had overseen two chartered flights of migrants from Texas to Sacramento, California, last week, drawing sharp rebukes from California Governor Gavin Newsom and other officials.

“This policy has been debated now for a long time," DeSantis said. “I think it’s something that has been very, very effective.”

DeSantis, a top contender in the Republican primary fight led by front-runner Donald Trump, has made border security a focus of his campaign, accusing the Biden administration of lax immigration policies.

“This has been a massive dereliction of duty by the president,” DeSantis said at a meeting with law enforcement officials in Sierra Vista, Arizona, which sits close to the U.S. border with Mexico.

The victor of the Republican nominating contest will take on Democratic President Joe Biden in the November 2024 election.

DeSantis said the flights had diverted migrants from traveling to Florida and blamed liberal states such as California for policies that he said encouraged illegal migration.

Last year, DeSantis arranged to transport dozens of migrants from Texas to the Massachusetts vacation island of Martha’s Vineyard, a move that drew applause from Republican voters during DeSantis' three-state campaign swing last week.

Newsom, a Democrat, threatened DeSantis with kidnapping charges over last week’s flights, calling him a “small, pathetic man” on Twitter. California’s attorney general has said he is looking into potential civil or criminal liability for the flights.

Florida’s Division of Emergency Management said on Tuesday that the migrants traveled on the flights voluntarily. In its most recent session, the Florida legislature expanded the state’s migrant relocation program by an additional $12 million.

During his border event, DeSantis frequently spoke of the need to stem the flow of illegal drugs, including fentanyl, across the border, saying communities across the nation were being affected.

“Yes, it’s a border crisis, but it’s really an American crisis,” he said.

The border, DeSantis said, “just needs to be shut down.”

He announced that Florida would partner with sheriffs and "like-minded" governors nationwide to provide resources to help secure the border.

The Biden administration on Tuesday said border crossings had dropped by more than 70% since the lifting of a pandemic-era order known as Title 42, in spite of Republican concerns that it would result in a flood of new migrations.

The administration credited the drop to tougher penalties for illegal border-crossers along with new administrative pathways for migrants seeking asylum.

(Reporting by James Oliphant in Washington; Editing by Colleen Jenkins and Deepa Babington)