An Italian opposition parliamentarian has accused his government of lying about the Sicilian fishermen who were detained in Benghazi.

"The government lied about the issue of the Mazara del Vallo fishermen, and despite assurances about their health conditions in recent months, in response to our questions and protests, the fishermen confirmed that they have gone through horrific situations," the Italian MP Lorenzo Viviani said.

The MP -who is in the fishing committee of the Italian Parliament- demanded, in Monday's memo, Prime Minister Giuseppe Conte and Foreign Minister Luigi Di Maio, to be more transparent about the negotiations that led to the release of the fishermen.

"The negotiations show that Italy is moving more and more towards a secondary position on the Mediterranean chessboard, a fact that would lead to a repetition of such abuse," as he put it.

A Tunisian fisherman, who was among the recently released Italian fishermen, had confirmed in statements to the Tunisian press that they had been severely ill-treated, despite not being subjected to physical violence.