Barack Obama heads to Israel for first time as president

US president Barack Obama is flying to Israel for his first trip there in his official head of state capacity, amid protests and tight security in Israel and the Palestinian territories.

The war in Syria and concerns over Iran's nuclear ambitions will loom large in talks. But US officials are trying to downplay expectations that Obama will seek to make significant headway on restarting the Israel-Palestinian peace process.

Settlement supporters are a big force in Israel's new coalition government, and Israelis are more preoccupied with instability in the wider Middle East region than with breathing new life into the peace process, which broke down in 2010 amid a dispute over continued Israeli settlement construction.

Obama is scheduled to meet Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas during his three-day visit, while US Secretary of State John Kerry travelled ahead of him to prepare for the president's arrival.

In the US, Obama has been criticised for not having visited Israel in his first term as president, with some saying it shows he is not close enough to the country.

That is despite his administration's repeated assertion that the two countries share an "unbreakable alliance".

Thousands of Israeli and Palestinian security officers have been assembled in Jerusalem and the Palestinians' de facto capital in the West Bank, Ramallah, ahead of his trip.

The state of the economy and social issues dominated Israel's last election, and the president has said he is not going to the region bearing any grand peace plan.

But with warnings that time is running out for a two-state solution, some still think he will try to lay the ground for some greater effort to restart talks, our correspondent says.

The president's relationship with Netanyahu has been notoriously frosty and one recent opinion poll suggested a mere 10% of the Israeli public had a favourable opinion of the US president.

The main event of this trip is a speech to the Israeli people - his main task is to build bridges and improve his image, which could give him more leverage over the new Israeli government, our correspondent adds.

On Tuesday Palestinian protesters gathered in Ramallah and Bethlehem, some throwing shoes at images of the president and others driving over his portrait, reports said.

Demonstrator Huwaida Arraf told Reuters news agency that Obama's visit was "a slap in the face".

"People are angry and disappointed that this far into his presidency, Obama has done nothing, and aid to Israel's occupation continues to flow," he said.

Meanwhile, Israeli demonstrators gathered in Jerusalem to demand Obama free Jonathan Pollard, imprisoned in the US in 1987 for spying for Israel.

"Let my people go," said one banner.