Israeli Prime Minister Ehud Olmert has pledged to seek parliamentary approval for any significant agreement with the Palestinians, including the joint declaration of principles he is trying to reach ahead of a U.S.-sponsored Mideast conference later this year, according to a letter released Monday.

Approval would be far from automatic if the declaration commits Israel to giving up parts of Jerusalem or other main concessions sought by the Palestinians. Hawkish parties in Olmert's coalition have threatened to bring his government down if he agrees to such steps.

Attorney General Meni Mazuz forwarded the contents of Olmert's letter to a leader of the hard-line Likud opposition party, Gideon Saar, in which Olmert made the commitment for parliamentary approval.

In the letter, Olmert pledged that "any document that expresses the state of Israel's commitment regarding issues of political-military importance, whether in the form of an agreement or in the form of a joint declaration ... will be brought before the Knesset," Israel's parliament, according to Mazuz's office.

However, Mazuz said Olmert qualified that promise by saying that it was not clear the declaration would go far enough to require a vote.

Mazuz's statement reflects the main disagreement between Israel and the Palestinians over the preparations for the conference, called by President Bush to promote peace efforts between the sides.

The Palestinians want a detailed declaration about the main issues that need to be resolved in a treaty, including the borders of a Palestinian state, the status of Jerusalem and the fate of Palestinian refugees. The Palestinians also want a timetable for creating a state.

Partly because of his precarious political situation, Olmert prefers a vague document with considerable room to maneuver, hoping the outcome of the conference in Annapolis, Md., would be the resumption of negotiations. Peace talks have been stalled for seven years despite international efforts to jump-start them.

Of all the issues, Jerusalem is the most sensitive. Both sides claim sovereignty over a disputed holy site in the Old City and have shown no willingness to compromise. Israel captured east Jerusalem, including the Old City, in the 1967 Mideast war.

Two hard-line parties have threatened to bolt Olmert's governing coalition if he addresses Jerusalem or other key issues at the Annapolis conference.

If they follow through on the threat, Olmert would lose his majority in parliament and might have to resign. That would freeze peace efforts for months during an Israeli election campaign. Olmert's pledge to let the parliament vote on concessions might be a way to pacify his coalition partners.

Palestinians warn that failure of the Annapolis meeting to produce an agreement could spark a new round of Mideast violence.

Peace efforts have been complicated by the Hamas militant group's violent takeover of the Gaza Strip in June.

In the wake of the takeover, moderate Palestinian President Mahmoud Abbas formed a new pro-Western government without Hamas. While this has enabled the West to re-engage the Palestinian leadership, Abbas controls only the West Bank and has little influence over Gaza. The Palestinians want their future state to include Gaza and the West Bank.

Secretary of State Condoleezza Rice has made frequent trips to the region in recent months, intensifying her involvement in preparation for the conference.

She has been trying to nudge the sides closer together, urging Israel to make specific commitments in a pre-conference document while calling on the Palestinians to moderate their demands. Rice is expected to return to the region in early November.

Violence erupted early Monday at an Israeli desert prison when about 1,000 Palestinian prisoners rioted, attacking guards, torching the tents where they are housed and leaving 30 people injured, a prison spokesman said.

The violence broke out when guards began searching prisoners' bunks for contraband, Israel Prisons Authority spokesman Ian Domnitz said. About 2,200 Palestinian prisoners are serving sentences for security offenses at the Ketziot prison, he said.

Prisoners set fire to 10 tents and attacked guards, wounding 15 of them, Domnitz said. Prison officers moved in to quell the riot, injuring 15 prisoners, one critically, he said.