John Kerry
John KerryReuters

US officials warned Wednesday that patience with "crazy" Israeli criticism of would-be-peacemaker John Kerry had snapped, using unprecedentedly rude language to characterize an alleged transcript of the most recent phone conversation between President Barack Obama and Prime Minister Binyamin Netanyahu.

Relations between Israel and the United States have been testy in recent days after Kerry returned from a mission to the Middle East to try to broker a ceasefire between the Israelis and Hamas militants.

Anonymous Israeli officials have hit out at Kerry's truce proposal, calling it "a strategic terrorist attack" and criticizing it for being a "Hamas wish-list" including moves to lift a long-standing blockade of Gaza while failing to address Israel's security concerns, such as Hamas rocket fire and a network of underground tunnels. State Department Spokeswoman Marie Harf called these accusations "offensive and absurd" Wednesday.

And on Tuesday an alleged transcript of a call between US President Barack Obama and Israeli Prime Minister Binyamin Netanyahu went viral on social media.

Stressing the "unprecedented" US support for the Jewish state, Harf hit out at Israeli elites' "offensive and absurd" claims that Kerry backs Hamas.

She rubbished the transcript as "complete cr*p," adding "there's clearly people... who are putting out false and defamatory and absurd information."

"I don't know what else you can assume about the intentions except that they're designed to hurt our relationship," she added.

Washington, which has provided billions in military aid to Israel, including funding the Iron Dome shield protecting the country from Hamas rockets, was "very committed" to the security of the Jewish state, which is "why these vicious attacks on the secretary are just crazy," she added.

Israel, too, said that the leaked transcript "bore no resemblance to reality."