Italy’s ambassador to Egypt has left Cairo after Rome recalled him over a lack of progress in the probe into the murder of an Italian student, according to an airport official and a diplomatic source.

Italy, a key ally of Egyptian president Abdel Fatah al-Sisi’s regime, recalled Maurizio Massari on Sunday after last week’s inconclusive meetings between Italian investigators and an Egyptian team that visited Rome to present their findings into Giulio Regeni’s murder.

Regeni, a 28-year-old Cambridge University PhD student, had been researching labour unions when he disappeared on 25 January from central Cairo. His mutilated body was found more than a week later by the side of a road on the outskirts of the Egyptian capital.

During the meetings in Rome, Italy had demanded thousands of phone records to investigate the murder, which Egypt’s assistant state prosecutor Mostafa Suleiman said was a demand that “violates the Egyptian constitution”.

Suleiman, who headed the Egyptian team that visited Rome, said the Italian investigators “conditioned further judicial cooperation on this demand” which his team flatly refused. Suleiman said the Italian investigators also demanded CCTV footage of the area from where Regeni had disappeared. He said the footage had been automatically deleted by then.

On Sunday, Massari left for Rome after Italy recalled him for consultations, an Italian diplomatic source told AFP. An airport official also confirmed he had departed Cairo.

Italian officials have greeted Egypt’s explanations concerning Regeni’s murder with outright scepticism. They suspect he was killed by elements in the Egyptian security services, an accusation which Cairo has steadfastly denied.