Italy recalled its ambassador to Egypt on Friday in protest over what it said was a lack of progress in the investigation into the brutal murder of an Italian student in Cairo two months ago.
Ambassador Maurizio Massari was summoned to Rome "for consultations" on "an urgent assessment of the most opportune moves to renew efforts to find out the truth on the barbarous murder of Giulio Regeni", Foreign Minister Paolo Gentiloni said.
The move came after two days of talks between visiting Egyptian and Italian investigators in Rome ended without a resolution of mounting tensions between the two countries.
"We want only one thing, the truth about what happened to Giulio," Gentiloni said in a tweet.
READ MORE: Egypt prosecutors in Rome to discuss Giulio Regeni case
Regeni was in Cairo doing research for his doctoral thesis on trade unions in Egypt on behalf of Britain's University of Cambridge.
He was last seen on January 25, a day on which Egypt's security services were on high alert for possible demonstrations to mark the fifth anniversary of the uprising that ousted longtime ruler Hosni Mubarak.
Seven days later, the 28-year-old was found dead on the side of a motorway on the outskirts of Cairo, with what Italian officials say were clear signs of torture.
Egyptian authorities initially blamed the death on a road accident.
Several other explanations for the murder were offered by Egyptian officials and media in the following weeks - most recently that Regeni was the victim of a gang of robbers - but none of them was
judged credible by Italian authorities.
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A statement by the Rome prosecutor in charge of the case said that the Egyptians had handed over phone records of two of Regeni's Italian friends who were in Cairo at the time of his disappearance, as well as photos taken on the day his body was discovered.
The statement made no mention of CCTV footage of the neighbourhood from which Regeni disappeared, which the Italians had asked to see, or whether Regeni was under surveillance before his abduction.
The Egyptians indicated they were still considering the possibility that Regeni was abducted by an anti-foreigner criminal gang whose members all died in a police shoot-out last month.
The Italian prosecutor "reiterated his conviction that there are no elements to directly link the gang to the torture and death of Giulio Regeni", the statement said.
The killing has jeopardised relations between the two countries, with Italy warning this week of diplomatic retaliation after complaining that Egypt was dragging its feet over the affair.