Israeli Prime Minister Benjamin Netanyahu was due in Washington Sunday on what he has called a "historic" quest to stop an international nuclear deal with Iran that the United States is determined to pursue.

Netanyahu's controversial 48-hour visit has stoked discord with US President Barack Obama and brought bilateral relations to their lowest point in years.

The speech by the Israeli leader aims to drum up last-minute support to halt a possible world deal with Iran over its nuclear program.

It has infuriated the White House and prominent Democrats because the speech was set up by congressional Republicans without the knowledge of the president, violating typical protocol.

Several leading members of the America's political establishment have announced they plan not to attend Tuesday's address to a joint session of the US Congress.

For his part, 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."

Secretary of State John Kerry -- who will be leaving Washington at almost exactly the same time that Netanyahu is arriving -- on Sunday insisted that the United States is eager to avoid politicizing the controversial visit.

- Kerry: US, Israel 'closer than ever'-

"The Prime Minister of Israel is welcome to speak in the United States obviously and we have a closer relationship with Israel right now in terms of security than in any time in history," Kerry told ABC television's "This Week" program.

"We don't want to see this turned into some great political football," Kerry said, just hours before Netanyahu was due to arrive in Washington.

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 March 31 target for a framework deal with Iran. Negotiators intend to pin down the technical details of a comprehensive agreement by a June 30 deadline.

The so-called P5+1 group of Britain, China, France, Russia, the United States and Germany are trying to strike an accord that would prevent Tehran from developing a nuclear bomb.

The next round of talks is to start next week in Switzerland.

In return, the West would ease punishing sanctions imposed on Tehran over its nuclear program, which Iran insists is purely civilian.

Netanyahu's visit also comes about two weeks before a March 17 general election in Israel in which he is hoping to win a third consecutive term in office.

Kerry suggested to US television on Sunday that there were no hard feelings, despite the administration's ruffled feathers after the speech was announced.

"Obviously, it was odd if not unique that we learned of it from the Speaker of the House (John Boehner) and that the administration was not included in the process, but the administration is not seeking to politicize this," Kerry said.

"We want to recognize the main goal here is to prevent Iran from getting a nuclear weapon and on that Israel and the United States agree," the top US diplomat said.

Kerry added that the two allies "have an unparalleled close security relationship with Israel and we will continue to."

Those mollifying words were far gentler than remarks from the Obama administration just last week, when the president's national security adviser Susan Rice warned that the Netanyahu speech would be "destructive of the fabric of the relationship."

A string of Democratic lawmakers are voting with their feet, announcing they will not attend Netanyahu's speech.

US Vice President Joe Biden, who normally would be expected to preside over such an important ceremonial joint congressional session, also found pressing overseas business that he said would prevent him from attending Netanyahu's address.

Kerry has said that a week of overseas travel also will keep him away from the speech.

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