US Secretary of State John Kerry landed in Cairo early Sunday to lend US backing to a high-profile conference aiming to raise billions of dollars to help rebuild what the recent Zionist aggression devastated in Gaza.

US Secretary of State John Kerry landed in Cairo early Sunday to lend US backing to a high-profile conference aiming to raise billions of dollars to help rebuild what the recent Zionist aggression devastated in Gaza.

Some 50 countries are to attend the talks, with Palestinians hoping for $4 billion in global pledges, despite wariness from donors that without a full 'peace treaty' they may just be pouring money down the drain.

Kerry will also have a series of bilateral meetings on the sidelines of the conference, likely to focus on US efforts to build a coalition against extremist terrorists who have seized territory in Iraq and Syria.

The donor conference has been called to seek help for Gaza as Palestinians seek to rebuild their lives after a 50-day Israeli war against the Strip.

Many "had their homes bombed out and have been suffering under very difficult humanitarian conditions for the last several months," the US official said.