Four years after the mutilated body of the Italian doctoral student Giulio Regeni was discovered in Cairo, Italian politicians and officials are pinning hope for fresh information on an Italian parliamentary inquiry, as Egypt continues to obstruct investigations.

Regeni’s body was found on 3 February 2016, nine days after he had disappeared in the Egyptian capital. His mother, Paola, said later she only recognised his corpse by the “tip of his nose”, given the extensive torture he had endured. Widespread suspicions that Egyptian security forces were responsible for his disappearance and murder were reinforced in 2018 when Italian prosecutors named five officials as suspects.

Egypt’s state information service said in response that “Egyptian law does not recognise what is called ‘the record of suspects’.”

At a memorial service on 25 January in Regeni’s hometown of Fiumicello, Roberto Fico, the president of Italy’s lower house of parliament, read the names of the five officials listed as suspects in 2018.

“We have these names, and we will not stop. We cannot pretend nothing happened,” said Fico. “2020 must be the year of the truth, the year of Giulio Regeni. No more words; we need action now. This is what I said in Cairo to [the Egyptian president Abdel Fatah] al-Sisi, in a very tense meeting. Unfortunately, we didn’t obtain what we were hoping for. The Egyptians went back on their words; they deceived us.”

He added: “Our country has to continue to demand the truth from the Egyptians … We want concrete actions, especially regarding judicial cooperation.”

Fico believes other European countries should add to the pressure on Egypt. “For this reason, the European parliament took up the case, and consequently I informed my German counterpart, [Wolfgang] Schäuble. I expect the same support from the British authorities. I spoke about the situation with Speaker [John] Bercow a few months ago, and I will broach the subject with his successor as well,” he said.

The Egyptian public prosecutor Gen Hamada al-Sawy ordered the establishment of a new team to oversee Egypt’s investigation of the case last month. This followed a visit by Italian investigators to Egypt, whose prosecutors “agreed to continue fruitful judicial cooperation”, according to Egyptian state media.

But reassurances from the Egyptian side followed long-term efforts to obscure an investigation. Multiple theories about Regeni’s disappearance provided by the Egyptian authorities were rejected by their Italian counterparts. In 2016, Egypt’s former public prosecutor admitted there were “doubts” about the involvement of five men accused by Egypt of connection to Regeni’s kidnap who were gunned down by Egyptian security forces.

Extensive efforts to obtain CCTV footage of the Cairo metro from the night when Regeni disappeared were moot, after footage provided by the Egyptian side contained “unexplained gaps”, according to Italian prosecutors.

Mohamed Lotfy from Cairo NGO the Egyptian Commission for Rights and Freedoms, whose lawyers act as the Regeni family’s Egyptian legal counsel, said the Italian parliamentary inquiry would assist their team, highlighting information not provided to them by Egypt’s judiciary. “We’re still struggling to get parts of the case file,” he said.

Lotfy remained hopeful about the parliamentary inquiry and what the reshuffle inside the Egyptian public prosecutor’s office could mean for their ability to make progress. But in the four years since Regeni’s murder, many of their staff have been detained and their offices raided due to their involvement with the case. “The reprisals against our team have not stopped,” he said.

For observers, new information can only emerge from the parliamentary inquiry. Erasmo Palazzotto, the president of the inquiry, said he was gathering more information on the circumstances of Regeni’s kidnap.

Michele Prestipino, Rome’s chief prosecutor, said: “There is difficulty in coordinating our investigation with that of the Egyptians, and it is made increasingly challenging because there is no accord on judicial cooperation between the two countries. Despite these difficulties, we can affirm that significantly positive results have already been reached.”