El Salvador offered to house some of America’s most violent convicted criminals, including U.S. citizens, in its mega-prison known as the Terrorism Confinement Center (CECOT) for a fee in an “unprecedented” deal.

El Salvador’s President Nayib Bukele announced the unusual proposal with his North American Counterpart via his X (formerly Twitter) account.

El Salvaodor’s supermax prison is known as one of the harshest and most heavily policed detention facilities in the world.

The news comes following his meeting with the US Secretary of State, Marco Rubio on Monday evening CNN reports.

“In an act of extraordinary friendship to our country … (El Salvador) has agreed to the most unprecedented and extraordinary migratory agreement anywhere in the world,” Rubio told reporters Monday as per CNN.

The proposed arrangement also includes US Citizens and other nationalities and deportees sent back to the country.

It is unclear whether the US government will or is considering taking up the offer, especially with questions around the legality of such a move.