According to US officials, Egypt, Jordan and Morocco will attend a conference led by U.S. in Bahrain this month.
However, U.S. officials have not decided the timing for the second phase of their initiative yet.
The conference aims to boost the Palestinian economy as part of a coming U.S. peace plan.
Egypt and Jordan have always played an important historical role in Israeli-Palestinian peace issue.
A White House official said that Saudi Arabia, Qatar and the United Arab Emirates have previously confirmed their participation.
Furthermore, global financial bodies such as the International Monetary Fund (IMF) and World Bank will be a part of the conference.