The UN-backed government in Libya has said it ordered the arrest of a man described as one of the world’s most notorious human traffickers who was this month revealed to have attended meetings between Italian officials and a Libyan delegation to discuss controls on migration flows from north Africa.

In a note released on Monday by the interior ministry in Tripoli, authorities said Abd al-Rahman Milad, described by the UN security council as a ruthless human trafficker suspected of drowning dozens of people, was “a wanted man and an arrest warrant was issued against him”.

The alleged trafficker’s presence at meetings in Sicily and Rome in May 2017, first documented by the newspaper Avvenire, has prompted criticism of the then interior minister, Marco Minniti. Three months earlier, Minniti had signed a memorandum with the leader of Libya’s government, Fayez al-Sarraj, for cooperation with the Libyan coastguard, which included the provision of four patrol vessels.

The deal empowered the Libyan coastguard to intercept migrant boats at sea and redirect them to Libya, where aid agencies say refugees are abused and tortured.

The alleged trafficker, commonly known as Bija, was introduced at the meeting as “a commander of the Libyan coastguard”, Avvenire said. Minniti has denied any wrongdoing, saying Italy was unaware of the allegations of criminal activity against Bija at the time.

The issuing of the arrest warrant followed a recent video interview with the trafficker in the city of Zawiya, aired on Friday on the popular Italian television programme Propaganda Live. The government in Tripoli said the warrant was originally issued in April but that it had been unable to execute it because conflict broke out in the capital.

Bija, who was wearing a coastguard uniform, told the investigative journalist Francesca Mannocchi that during his trip to Italy he had been invited to take part in meetings at the “ministry of justice and ministry of the interior in Rome”. When asked if he had met Minniti, Bija said: “I don’t know, maybe.”

The Italian journalists Nello Scavo, from Avvenire, who first documented Bija’s presence in Italy, and Nancy Porsia, who first wrote about the smuggler’s criminal activities early in 2017, have been given police protection in recent weeks.