"It's at a very critical stage right now," Ms. Ashrawi said, referring to the aid pledge.
Next on Mr. Cabezas' fund-raising mission is a trip to Spain to seek aid pledges.
The Clinton Administration will gather international donors in Washington later this month to present a new aid pledge for Palestinian-controlled areas.
Some donors, like Germany, have already responded by sharply scaling back their aid pledges.
No new aid pledges came from the meeting, held by the United Nation's Food and Agriculture Organisation.
Japanese officials attached new conditions today to the financial aid pledge Japan made last week to help Middle Eastern countries hurt by the trade embargo on Iraq.
The aid pledge, made in the Conservative election manifesto last year, was at the heart of Mr Cameron's attempts to change his party's image.
Other aid pledges total more than $200 million so far.
The American aid pledge represents no new money beyond that which had already been promised.
All told, the tsunami generated a record $13.6 billion in aid pledges, according to the United Nations.