Israeli Prime Minister Ehud Olmert and Palestinian President Mahmoud Abbas have agree to form three levels of negotiations over core issues of the Israeli-Palestinian conflict.

The agreement was made at the meeting held on Tuesday between the two leaders ahead of U.S. President George W Bush's upcoming visit.

The three-level model is comprised of talks on the following levels: Israeli Foreign Minister Tzipi Livni and head of the Palestinian negotiations team Ahmed Qureia will discuss the core issues in a direct dialogue first. And the negotiating teams will then discuss the issues in detail. In case of a disagreement, Abbas and Olmert will intervene.

According to local media, negotiations over the core issues will begin after Bush's visit to the region this week, while the remaining issues will be discussed in other committees.

Bush is due to visit Israel and the West Bank on Wednesday and Thursday as part of a regional tour that will cover seven countries in nine days.