A U.N. investigation into possible war crimes in Israel and Gaza will go ahead with or without Israel's cooperation, the chief investigator said Wednesday.

Israel regards the probe as "intrinsically flawed" because it was ordered by the U.N. Human Rights Council, which has an anti-Israel track record.

But Richard Goldstone, a veteran prosecutor of war crimes in Rwanda and former Yugoslavia, said he wants his team to bring a balanced approach to the January conflict and was upset that Israel has turned a deaf ear to his appeals for cooperation.

"I'm disappointed, and the members of the mission are disappointed, that we've had no positive response from the Israeli government," said Goldstone, a Jew with close ties to Israel.

He said the team wanted to start in Israel, visit the southern part of the country and town of Sderot, which was hit repeatedly by Palestinian rockets, and then enter Gaza "through the front door."

Goldstone says the team will travel to Gaza through Egypt if the Jewish state bars them.

U.N. Secretary-General Ban Ki-moon, who met with the investigators in Geneva on Wednesday, said he would press Israel to let Goldstone in.

"I expressed my strong support for his mission," Ban told The Associated Press. "I told him that I had discussed with the Israeli government, particularly President Shimon Peres."

He said he had urged Peres to extend his full cooperation for the mission.

"I have not yet received a reply directly (from the Israelis), but I am going to continue to discuss this with them," Ban said.

Israel has been at odds with the 47-nation U.N. Human Rights Council since its creation three years ago. It refused to cooperate with an earlier Gaza probe the council assigned Nobel Peace Prize laureate Desmond Tutu to head.

Israel has objected to the current investigation because the team has been instructed only to investigate alleged abuses by Israelis, though Goldstone says he will examine conduct by both sides.

"We think that the mandate is intrinsically flawed and defective and therefore this commission will never be able to do a proper job, whatever good intentions its head may have," Israeli Foreign Ministry spokesman Yigal Palmor said Wednesday in Jerusalem.

He would not say whether the U.N. team members would be allowed to enter Israel.

The council has a large contingent of members from Islamic countries, and Israel regards the Geneva body as biased.

Israel launched its offensive against Gaza on Dec. 27 in a bid to halt eight years of rocket fire into its southern territory and deal a heavy blow to the Hamas militant group.

The three-week operation killed more than 1,400 Palestinians, including more than 900 civilians, according to Palestinian officials and human rights groups. It also destroyed thousands of homes and heavily damaged Gaza's infrastructure.

Israel says the death toll was lower than that and most of the dead were Hamas militants. It blames Hamas for the civilian casualties, saying the militants used schools, mosques and residential areas for cover. Thirteen Israelis were killed during the fighting.

Middle East warfare presents a new challenge to Goldstone, a trustee of the Hebrew University of Jerusalem who over the years has "taken a deep interest in Israel (and) in what happens in Israel."

Goldstone, an opponent of apartheid in his native South Africa where he served as a justice of the South African Constitutional Court, was named in 1994 to be U.N. chief prosecutor for war crimes in former Yugoslavia and genocide in Rwanda.

He has been widely credited with being impartial, letting the chips fall where they may.

Goldstone said the team was still making contacts and didn't have a travel schedule yet, but needs to finish its field work by the end of June.

The independent team includes Christine Chinkin, professor of international law at the London School of Economics; Hina Jilani, a human rights advocate from Pakistan; and Desmond Travers, a former officer in the Irish Armed Forces with expertise on international criminal investigations.