Obama heads to Israel amid low expectations

The White House has touted the US-funded system, which has helped protect Israelis from Hamas rocket attacks from Gaza, as a prime example of Obama's commitment to Israel's security -- a message likely to be rammed home during the trip.

Obama, accompanied by his new secretary of state, John Kerry, will hold lengthy talks with Netanyahu later on Wednesday, with Iran expected to top the agenda.

US President Barack Obama sits aboard Marine One as he departs for travel to Israel, from the White House in Washington March 19, 2013. [Photo/Agencies]

Israel and the United States agree that Iran should never get a nuclear bomb, dismissing Tehran's assertion that its atomic programme is peaceful. However, the two allies are at odds over how fast the clock is ticking down on the need for preventative military action should diplomacy fail.

US officials say Obama will urge further patience, with Washington worried that a threatened Israeli unilateral strike might drag the United States into another Middle East war.

Obama, who has said he is coming to listen, will fly on Thursday by helicopter the short distance between Jerusalem and the West Bank city of Ramallah to meet Abbas.

Direct negotiations between Israel and the Palestinians broke down in 2010 over the issue of Jewish settlement building in the West Bank, and Abbas's allies have expressed bitter disappointment over the lack of fresh US moves.

"It's not a positive visit," said Wasel Abu Yousef, a senior official in the Palestine Liberation Organization, led by Abbas.

In Ramallah on Tuesday, Palestinian police scuffled with scores of demonstrators protesting against Obama's visit.

Although Netanyahu repeated this week that he was ready to make "a historic compromise" to achieve peace, his new cabinet has several pro-settler ministers fervently opposed to halting settlements on land Palestinians want to establish their state.

Dennis Ross, Obama's former Middle East adviser, said the president was right to tread cautiously when peace prospects were dim and Israelis more focused on what they see as greater threats presented by Iran and the war in neighbouring Syria.

"What you don't want to do at a time when there's enormous disbelief on the part of both parties is to do something that will fail," Ross said.