A United Nations investigator says his probe of possible war crimes by Israel and Hamas is unlikely to lead to any prosecutions.

The investigation was in response to last year's war in Gaza.

Meanwhile, George Mitchell, President Barack Obama's special envoy to the Middle East, is in the region pushing for a quick restart of peace talks.

His trip follows Obama's endorsement of a Palestinian state and demands that the Israelis halt further construction in the West Bank.

Mitchell has met with Israeli Defense Minister Ehud Barak and is scheduled to see Prime Minister Benjamin Netanyahu.

Later he will travel to Beirut and Damascus.