US calls Abbas' speech about 'genocidal war' at UN 'offensive'

The United States slammed Palestinian leader Mahmoud Abbas' speech at the United Nations, saying it was offensive and undermined peace efforts.

Speaking at the UN General Assembly in New York, Abbas vowed to seek war-crimes prosecutions against Israel over what he called the 50-day "war of genocide" in Gaza that killed 2,140 Palestinians, mostly civilians, and left the enclave in ruins.

"There is an occupation that must end now. There is a people that must be freed immediately. The hour of independence of the state of Palestine has arrived," he said.

He did not set a deadline for fast-tracking to Palestinian statehood, after aides suggested they were eyeing 2017 as a possible date.

US State Department spokeswoman Jen Psaki called the speech "deeply disappointing".

"President Abbas' speech today included offensive characterisations ... Such provocative statements are counterproductive and undermine efforts to create a positive atmosphere and restore trust between the parties," she said.