Israel's PM Ehud Olmert (l) and Palestinian President Mahmud Abbas  before a meeting in Jerusalem, 05 May 2008

A senior Israeli official says the government has made "significant progress" in talks with the Palestinians on drawing the borders of a future Palestinian state.

The official, who asked not to be identified, told reporters Israeli Prime Minister Ehud Olmert and Palestinian President Mahmoud Abbas discussed the border issue Monday in Jerusalem. Officials from both sides say negotiators have begun exchanging maps.

Israeli government spokesman Mark Regev says Monday's talks were perhaps the most serious the two sides have ever had. Palestinian negotiator Saeb Erekat described the Olmert-Abbas meeting as "deep and serious."

The talks came hours after U.S. Secretary of State Condoleezza Rice ended a three-day visit to the region. Rice said the U.S. will send monitors to the West Bank to observe the removal of Israeli roadblocks and to determine the impact on Palestinian movement.

Rice has said Washington is interested not just in the quantity of roadblocks Israel removes, but also in the steps taken by Israel to improve the everyday lives of Palestinians.

In another development, Israel said it will bar Palestinians from entering the country from early Tuesday until Friday, as part of security measures for its 60th anniversary celebration. Israel regularly closes its crossings with the West Bank and Gaza during national holidays, citing security concerns.

Also Monday, the United Nations relief agency for Palestinian refugees said it has received enough fuel from Israel to continue aid operations in the Gaza Strip for another 20 days.

The U.N. agency warned Sunday that it would have to suspend operations in Gaza because of a lack of fuel for its vehicles. Gaza has been suffering fuel shortages because of Israeli cutbacks in fuel supplies to the territory and a strike by Palestinian fuel distributors.

Some information for this report was provided by AFP, AP and Reuters.