The government of Eswatini said on Thursday it did not have any agreement with the United States to receive Kilmar Abrego, who President Donald Trump's administration said last week could be deported to the small African state.

"The Government of Eswatini has not received any communication regarding this person," government spokesperson Thabile Mdluli told Reuters.

"Any proposal to send more deportees to Eswatini will be discussed between the governments of Eswatini and the United States of America prior to initiating processes, and the country will be properly informed," Mdluli added in a text message.

The Trump administration has sought to deport more migrants to so-called "third countries," saying the step is necessary if their home countries will not accept them. Critics have questioned that rationale.

Eswatini accepted five third-country deportees from the United States in July, for which it is facing a court challenge by local human rights activists who have called their government's secretive deal with the Trump administration illegal.

Abrego, whose arrest in March and subsequent fight to stay in the United States have become a flashpoint in Trump's immigration crackdown, is originally from El Salvador and is currently being held in an immigration detention centre in Virginia.

A sheet metal worker who entered the United States illegally, Abrego had been living in Maryland with his wife, their child and two of her children - all of whom are American citizens - until he was arrested, accused of being a gang member and sent to a prison in El Salvador despite a U.S. judge's ordering prohibiting his deportation to his native country.

A September 5 email from a U.S. Department of Homeland Security official to Abrego's lawyers said: "We hereby notify you that your new country of removal is Eswatini." The official said the change was made because Abrego, 30, had stated that he feared persecution or torture in Uganda, previously designated for his deportation. Abrego has no ties to Eswatini.

In response to a request for comment, a senior Trump administration official referenced U.S. government allegations against Abrego, including criminal charges related to migrant smuggling, and said he would be deported, even if it was to another nation.

"We are not going to allow this public safety threat to remain in our country," the official said.

Abrego has pleaded not guilty.