JERUSALEM (Reuters) - Israeli Prime Minister Ehud Olmert sought wide Arab support on Monday for a U.S.-led peace conference by agreeing to release 441 Palestinian prisoners and reaffirming a pledge not to build new Jewish settlements.

Olmert held talks in Jerusalem with Palestinian President Mahmoud Abbas in a last-ditch bid to narrow differences a week ahead of the Annapolis, Maryland meeting.

Olmert did not say in earlier remarks to his cabinet if he would freeze construction within existing settlements in the occupied West Bank, as sought by the Palestinians and the United States. A senior Palestinian negotiator, latching on to the uncertainty, called Olmert's comments "nonsense".

"Let's be honest. We committed ourselves in the 'road map' not to build new settlements," Olmert said, referring to a stalled 2003 peace plan promoted by Washington.

"There will be no new settlements and no land confiscations" from the Palestinians, he told ministers.

Israel has not built a new settlement in the West Bank in nearly 10 years but has pressed on with construction in existing ones. In addition, settlers have set up several dozen hilltop outposts without government approval.

Olmert repeated at the cabinet session a long-standing promise to remove the outposts, but again set no date.

In a gesture to Abbas, he also won cabinet approval to release 441 Palestinian prisoners, a government official said.

All were members of Abbas's Fatah faction "without blood on their hands" and could go free as early as Friday after a review of a release list by a ministerial committee, the official said. Abbas had wanted 2,000 freed.

SAUDI PARTICIPATION

Saudi Arabia, which has not said whether it would attend the November 26-27 conference, had demanded a "freeze of settlements" before the meeting. It was unclear whether Olmert's remarks would go far enough to persuade Riyadh to participate.

"What Olmert announced today is nonsense," senior Palestinian negotiator Saeb Erekat said. "Olmert has to understand he either declares a full settlement freeze in all occupied areas including East Jerusalem, or it's nothing."

The road map calls for a freeze to "all settlement activity", including "natural growth", a reference to building in existing settlements to accommodate growing families.

"If Olmert does not halt 'natural growth' then nothing has changed," said Nabil Abu Rdainah, an Abbas aide.

About 270,000 Jewish settlers live among 2.5 million West Bank Palestinians. The World Court has branded all settlements on land captured by Israel in a 1967 war as illegal.

Abbas's chief negotiator said Israeli and Palestinian teams had failed to make progress on a pre-conference joint document that would address in general terms core issues such as borders and the future of Jerusalem and Palestinian refugees.

In a surprise announcement, Olmert's office said the prime minister planned to go to Egypt on Tuesday for talks with President Hosni Mubarak.

His trip appeared to be part of efforts to ensure broad Arab participation in the Annapolis meeting, a launching pad for formal talks on Palestinian statehood. Arab League foreign ministers meet in Cairo on Friday to decide whether to attend.

U.S. and Israeli officials said a joint document was not a precondition for the gathering, a chance for President George W. Bush, saddled with the legacy of the unpopular war in Iraq, to revive Israeli-Palestinian peacemaking before he leaves office.

Like Bush and Abbas, Olmert has been weakened politically. He faces police investigations over alleged corruption, which he has denied, and the results before the end of the year of an official inquiry into his handling of the 2006 Lebanon war.