JERUSALEM: Israel braced on Wednesday for what is expected to be a bruising UN debate on a report that accuses the Jewish state and Hamas of war crimes during its Gaza offensive at the turn of the year.

The UN Security Council was expected to discuss the so-called Goldstone report later on Wednesday at its regular monthly meeting on the Middle East, a day before the UN Human Rights Council reopens its own debate in Geneva.

The UN mandated fact-finding mission headed by respected South African judge Richard Goldstone drew sharp criticism from Israel, which reiterated on Wednesday that adopting the report would scupper any chance of restarting Middle East peace talks.

"It's not reassuring that such a report can be taken seriously by democratic countries, as it is a completely unrealistic, biased and preposterous," foreign ministry spokesman Yigal Palmor said.

The report recommends that its conclusions be forwarded to the International Criminal Court prosecutor in The Hague if Israel and the Palestinian Islamist movement Hamas fail to carry out credible investigations within six months.

Palmor said such a move "risks torpedoing the launch of peace talks and creates a dangerous precedent for any country that wants to defend itself against terrorist attacks."

Israel did not cooperate with the Goldstone team, saying the mission's mandate was biased against the Jewish state from the outset.

Israel's UN ambassador Gabriela Shalev, meanwhile, said her country was counting on its main ally Washington in case the report comes to a vote before the Security Council, where the United States wields veto power.

"Secretary of State Hillary Clinton has said that the United States will impose their veto in case of a vote by the Security Council," she told army radio.

And Defence Minister Ehud Barak spoke by phone to the foreign ministers of Britain, France, Norway and Spain and told them that adoption of the report "would seriously hurt our efforts to deal with terrorism."

"The Goldstone report is a deceitful, distorted and biased report that encourages terror. Adopting it would encourage terror all over the world," Barak's office quoted him as saying in a statement.

Discord over the Goldstone report has also deepened the divide between the two main Palestinian factions after the UN Human Rights Council in Geneva agreed on October 2 to defer a vote on the report.

The decision came after the Palestinian delegation, appointed by Palestinian president Mahmud Abbas of Fatah, dropped its insistance on an immediate vote.

Abbas faced a hail of criticism both at home and abroad over the decision, with Hamas accusing him of "betraying" the Palestinian victims of the Gaza war and asking that the signing of a long-delayed reconciliation deal between the two factions be postponed.

The beleaguered president defended his decision, but in the face of the outrage made an about-turn.

At the request of the Palestinian delegation, the Geneva-based UN Human Rights Council was also to hold a special session on Thursday on the situation in the Palestinian territories and east Jerusalem.