Italian judges ruled Friday against the detention of the first migrants sent for processing in Albania, dealing a major blow to a flagship policy of Giorgia Meloni's hard-right government.
Rome has repeatedly boasted that multiple EU countries are interested in the scheme as a way of processing asylum requests in countries outside the bloc, and Brussels has been watching closely.
But just days after the plan went live on Monday, the first group of migrants sent to non-EU Albania will have to leave again.
The judges ruled on the detention of a dozen men from Bangladesh and Egypt picked up in the Mediterranean and transferred by an Italian naval vessel on Monday.
They arrived at one of two Italian-run migrant centres in Albania on Wednesday.
The court said a recent ruling by the European Court of Justice meant the men do not meet the criteria for detention in Albania, and will instead have to be brought to Italy.
Meloni's post-fascist Brothers of Italy party slammed the "politicised judges", saying on X that the ruling made it "impossible" to send back irregular migrants.
It is the second blow to the controversial scheme, after four of the original 16 migrants transported this week were discovered to be "vulnerable" and had to be sent to Italy instead.
Opposition leader Elly Schlein, head of the centre-left Democratic Party, said they had known the judges would rule against the detentions "not because we are clairvoyants, but because we read the laws".
"Dismantle everything and apologise to the Italians," she told Meloni, adding that "far from being a model, the agreement you made with Albania... violates international, European and national law".
The November 2023 law states that migrants intercepted by Italian vessels at sea within Italy's search and rescue area be taken to Albania for processing, apart from minors, women or others considered vulnerable by law.
Meloni, elected in 2022 on a vow to reduce migrant boat crossings from North Africa, presented the scheme to around 10 other EU countries in Brussels Thursday, hailing it an "innovative" solution.
Her government hopes what she has called a "new, courageous, unprecedented path" will allow the majority of migrants to be rapidly repatriated.
To that end, Rome recently expanded to 22 countries its list of "safe" countries of origin -- defined as states where it deems there is no persecution, torture or threat of indiscriminate violence.
But on the list are nations that include areas not considered safe.
A recent ruling by the European Court of Justice stipulates that EU member states can only designate whole countries as safe, not parts.
Human rights groups have also questioned whether there will be sufficient protection for asylum seekers in the centres in Albania.
The two Italian centres operate under Italian law, with Italian security and staff, and judges hearing cases by video from Rome.
Amnesty International has called the centres a "cruel experiment (that) is a stain on the Italian government".
The project is set to last five years and will cost Italy an estimated 160 million euros ($175 million) a year.
