United States Secretary of State Marco Rubio met with El Salvador’s President Nayib Bukele and said the Central American nation has agreed to not only take in deported foreign nationals who committed crimes — but also jailed American citizens and permanent residents.

Rubio called the agreement “an act of extraordinary friendship,” on Monday.

“[Bukele] has agreed to accept for deportation any illegal alien in the United States who is a criminal, from any nationality — be they MS-13 or Tren de Aqua — and house them in his jails,” Rubio declared. “He has offered to house in his jails dangerous American criminals in custody in our country, including those of U.S. citizens and legal residents.”

Rubio called the deal the “most unprecedented and extraordinary migratory agreement anywhere in the world” and said, “no country has ever made an offer of friendship such as this.”

“We are profoundly grateful. I spoke to President Trump about this earlier today. And it’s just one more sign of what an incredible friend we have here in President Bukele and in the people of El Salvador,” Rubio said after they met for more than two-and-a-half hours.

“More details will be forthcoming” about the agreement struck between the United States and El Salvador, said Rubio, before taking an opportunity to praise Bukele’s leadership — describing his polarizing clampdown on El Salvador’s security as “difficult decisions” that had to be made.

President Trump has previously mused about sending repeated offenders abroad, even if they are lawfully in the United States. The president will now need to clear several legal hurdles, given that the Eighth Amendment prohibits “cruel and unusual punishments,” broadly considered to include exile.