Libya's prime minister met war crimes prosecutor Luis Moreno-Ocampo on Thursday and reassured him that Muammar Gaddafi's detained son is in good health and that his government is determined to give him a fair trial.

I assure the world that Saif (al-Islam) is being given a humanitarian treatment with respect and according to human rights guidelines, Abdurrahim El-Keib told reporters after meeting the International Criminal Court chief prosecutor, in Libya to investigate Gaddafi's son who is wanted by the ICC.

Earlier this month a senior defence lawyer at the ICC asked the court to report Libya to the U.N. Security Council over its failure to extradite Saif al-Islam to The Hague.

Xavier-Jean Keita said the wanted man had been physically attacked and was suffering dental pain.

The ICC issued an arrest warrant for Saif al-Islam in June 2011 after prosecutors accused him and others of involvement in the killing of protesters during the revolt that eventually toppled and killed his father.

But Libya says Gaddafi's British-educated son should face justice at home rather than stand trial in The Hague.

He was caught in November disguised as a Bedouin tribesman in the Sahara desert, months after telling his father's opponents they would be exterminated like rats.

He is still being held in a secret location in the town of Zintan, 160 km (100 miles) west of Tripoli by the former fighters who captured him and who have so far declined government requests to hand him over.

(Reporting By Hadeel Al-Shalchi; Editing by Robin Pomeroy)