Jerusalem ? As U.S. Secretary of State Condoleezza Rice wrapped up her latest Middle East mission, Palestinian officials conceded Monday that a timetable to finish negotiations leading to establishment of a Palestinian state will not be finalized before an upcoming U.S.-sponsored peace conference.

But Palestinian Authority President Mahmoud Abbas, after meeting with Rice in Ramallah, said negotiations carry their own non-negotiable deadline: the end of President Bush’s term in January 2009.

Rice’s visit ended on an upbeat note, however, with Abbas saying that there was “a real opportunity to achieve peace.”

Palestinian and Israeli negotiating teams continue to work on a joint pre-conference declaration of mutual goals.

Abbas and other Palestinian officials have hinted that they might skip the conference, which is scheduled for sometime in the next six weeks in Annapolis, Md., unless the joint statement includes specific proposals on core issues and a firm timeline for negotiations.

Israeli officials, backed by Rice, prefer to leave the specifics to long-term negotiations after the Annapolis conference.

On Monday, despite receiving almost none of what he demanded, Abbas indicated that he was committed to the process.

The generations-old Israeli-Palestinian conflict won’t be solved “in days or weeks or even months,” he said, “but we have hope. The negotiations are difficult and will continue to be difficult until the last moment.”

Rice sounded a similarly optimistic tone.

“We appear to be on course to prepare seriously for continuous ongoing negotiations,” she said. “The Palestinian people have waited a long time to achieve the dignity that comes from an independent state.”

A final date for the Annapolis conference hasn’t been set, and the U.S. has yet to issue formal invitations. America’s Arab allies, countries including Saudi Arabia and Egypt, have yet to commit formally to high-level representation. Their support is considered to be crucial to a successful conference.