Israeli Prime Minister Benjamin Netanyahu headed to Washington Sunday on what he said was a "historic" mission to try to stop a nuclear deal with Iran, an AFP correspondent reported.
The controversial 48-hour visit will see the Israeli leader addressing a joint session of the US Congress in a bid to garner last-minute support to halt an emerging world deal with Iran over its nuclear program, in a move which has infuriated the White House.
But Netanyahu, who will also address the annual policy conference of the pro-Israel AIPAC lobby, has refused to back down.
"I'm going to Washington on a fateful, even historic, mission," he told reporters on the tarmac at Ben Gurion airport near Tel Aviv shortly before his plane took off.
"I feel deep and sincere concern for the security of Israel's citizens and for the fate of the state and of all our people," he said.
"I will do everything in my power to ensure our future."
Netanyahu will address AIPAC before heading to Capitol Hill on Tuesday after which he will fly home.
In his remarks, Netanyahu made a veiled allusion to the controversy stoked by his visit, noting the upcoming Jewish holiday of Purim, which starts at sundown on Wednesday and remembers the biblical story of how the Jews were saved from the ancient Persians.
In the story, Queen Esther, the young Jewish wife of the Persian king, risks her life by appearing before him unannounced in order to expose the imminent threat to the Jewish people.
Israel believes Iran and world powers are likely to reach a deal that eases international sanctions on Tehran without applying sufficiently stringent safeguards to stop it developing nuclear weapons.
Netanyahu's trip comes just four weeks before a 31 March target for a framework deal, with negotiators intending to pin down the technical details of a comprehensive agreement by a 30 June deadline.
It also comes just two weeks before a 17 March general election in Israel in which Netanyahu is hoping to win a third consecutive term in office.
