Washington  - The United States on Friday sharply criticized a United Nations inquiry into this winter's war in Gaza for focussing too heavily on Israel's actions and minimizing Palestinian militant group Hamas' role in the conflict.

"Although the report addresses all sides of the conflict, its overwhelming focus is on the actions of Israel," State Department spokesman Ian Kelly said in Washington.

"While the report makes overly sweeping conclusions of fact and law with respect to Israel, its conclusions regarding Hamas's deplorable conduct and its failure to comply with international humanitarian law during the conflict are more general and tentative," he said.

The UN report by South African judge Richard Goldstone, released this week, found "strong evidence" that both Israel and Palestinian militants committed war crimes during three weeks of fighting in December and January.

Israeli politicians have roundly condemned the report, and the United States also backed their view that the inquiry was prejudiced against Israel from the start. The UN's Human Rights Council, which commissioned the report, set a "one-sided and unacceptable mandate for this fact-finding investigation," Kelly said.

The US also objected to Goldstone's call for the matter to be referred to the International Criminal Court at The Hague. The accusations should be dealt with by the Human Rights Council and Israeli's own courts, Kelly said.

"Israel has the democratic institutions to investigate and prosecute abuses, and we encourage it to use those institutions," he said.

Israel launched the offensive, which lasted 22 days, on December 27 in a bid to curb near-daily rocket and mortar shells from Gaza at its southern towns and villages. Human rights groups say some 1,400 Palestinians, mostly civilians, died in the war, while 13 Israelis were also killed.

Kelly said the Goldstone report shouldn't derail the "overriding goal" of restarting peace talks between the Israelis and Palestinians. US Middle East envoy George Mitchell failed to get an agreement to launch those talks during a three-day visit to the region this week.

The United States had hoped President Barack Obama could host a three-way meeting with Netanyahu and Palestinian President Mahmoud Abbas during a UN summit next week in New York. (dpa)