Israeli Prime Minister Benjamin Netanyahu told President Donald Trump last year that he was the "greatest friend Israel ever had in the White House."

Now, as Trump tries to finalize a deal to end the war with Iran, he's unloading on Netanyahu with rhetoric that no other American leader has dared to use publicly.

READ MORE: Israelis angry over U.S.-Iran peace deal lash out at Netanyahu

He claimed credit for Israel's existence — "without me, there would be no Israel" — and cursed his judgment in interviews. He even described him as "crazy."

Netanyahu's tenure as prime minister spans four U.S. presidents, and he's frustrated all of them at one point or another. But none has voiced that as openly as Trump, who started the conflict in tandem with Netanyahu.