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President Joe Biden's selection for ambassador to Israel, Jack Lew, told Senators at his confirmation hearing that he would work to ensure the US ally is not isolated internationally, but he faced tough questions from Republicans sceptical over his role in the 2015 nuclear deal.
At Wednesday's hearing, which was interrupted by protesters calling for a ceasefire in Gaza, Mr Lew also said he thought the October 7 Hamas attack on Israel was designed to “undermine” the US-backed push for Israel and Saudi Arabia to establish relations.
The US has not had an ambassador to Israel since Tom Nides left the post in July, leaving a hole in Washington's Middle East diplomatic presence as Israel responds to the Hamas attack and subsequent war in Gaza.
Senate Foreign Relations Committee Chairman Ben Cardin expedited Mr Lew's nomination hearing as Washington scurries to mitigate an intensifying Israel-Gaza war.
“We need someone there to reinforce the message that the United States stands shoulder to shoulder with the State of Israel in its response to the unprecedented (Hamas) terrorist attack,” said Mr Cardin.
Mr Lew, who was Treasury Secretary under Barack Obama, promised to “work to prevent other state or non-state actors from expanding this conflict to new fronts” and to “address the humanitarian crisis facing infants and millions of Gazans who are being used as human shields”.
He also vowed to continue Washington's policy of support for Israel and said he “firmly rejects” the Boycott, Divestment and Sanctions movement known as BDS.
“If confirmed, I will continue to oppose all efforts to isolate and delegitimise Israel internationally … and I will work to reinforce collective efforts to combat anti-Semitism,” said Mr Lew.
Mr Lew said he was “heartened” by humanitarian progress, as news broke during the hearing that Mr Biden and Israeli Prime Minister Benjamin Netanyahu had reached a deal opening $100 million in US humanitarian assistance for Gaza and the occupied West Bank.
Pro-ceasefire protesters identifying as Arab and Jewish repeatedly interrupted the confirmation hearing and were escorted out by police. Chants of “Stop the genocide of Palestinians,” and “Stop using (Jewish) grief” could be heard.
Republicans on the Democratic-majority committee largely stood opposed to Mr Lew's nomination, and the hearing was peppered with exchanges between the nominee and his critics.
“We need this thing filled, the problem is we need it filled with the right person,” said the committee's ranking member Jim Risch.
Conservatives grilled Mr Lew over his support of the 2015 Iran nuclear deal, which Israel strongly opposed, and accused Mr Biden's nominee of “misleading” the committee about the Iran nuclear deal negotiations during his time at the Treasury Department.
“Holding hands with Iran under the table doesn't work for me … I'm unpersuaded,” said Mr Risch, the committee's top Republican.
In the run-up to the October 7 Hamas attack, establishing ties between Saudi Arabia and Israel was at the forefront of the Biden administration's regional strategy.
“I dearly pray that we get back to that mission,” Mr Lew said.
The vote on the nomination is scheduled for next week.