Italy's justice minister yesterday promised a full investigation into allegations that governments in the early 1990s held secret negotiations with the Mafia to try to stop a spate of attacks on the state.

Angelino Alfano, speaking during a visit to the Sicilian capital, Palermo, said he hoped investigators would "do everything to ascertain the truth".

Mr Alfano spoke a day after Italy's chief anti-Mafia prosecutor, Paolo Grasso, caused a storm by telling an Italian newspaper he knew of contacts between the state and the Mafia in the early 1990s.

It was the first time anyone of Mr Grasso's level had stated so clearly that contacts took place between the crime group and the state in the early 1990s and his comments prompted demands for investigations and clarifications.

"I am mortified," said Antonio Di Pietro, a former magistrate who now heads the Italy of Values party. "The state was dealing with the Mafia to guarantee public peace while faithful servants of the state were being killed."

Mr Grasso's comments followed weeks of newspaper stories about a recently discovered "wish list" dictated by former Mafia "boss of bosses" Toto "the Beast" Riina before his arrest in 1993.

That 12-point list, written by Mr Riina's son on a scrap of paper while his father was still at large, listed 12 Mafia demands in exchange for stopping its attacks on the state.

In 1992, the year the note was believed to have been written and while the secret negotiations were alleged to have taken place, the Mafia killed two senior anti-mob magistrates, Giovanni Falcone and Paolo Borsellino in bomb attacks.

Authorities at the time feared more attacks but in 1993 Mr Riina was arrested after nearly a quarter of a century on the run, effectively ending any possibility of a deal.

Victims' relatives expressed outrage at the possibility that the state at the time wanted to deal with the Mafia at all.

"What Grasso said shocked me. Why are people only now talking of negotiations with the Mafia, 17 years later?" said Salvatore Borsellino, brother of the slain magistrate.

The contacts were believed to have started after Mr Falcone was killed in March, 1992, and Mr Grasso suggested the Mafia killed Mr Borsellino four months later to up the ante in the negotiations.