U.S. President Barack Obama telephoned Palestinian Authority President Mahmoud Abbas yesterday to try to persuade him to withdraw or soften the ultimatum he intends to send to Prime Minister Benjamin Netanyahu. This was the first conversation between the two since their relations soured half a year ago.

But Haaretz has learned that Abbas did not assent to the American president's request, vowing to deliver the letter to Netanyahu in the coming days.

Both a senior Palestinian official and a Western diplomat briefed about the conversation said that Obama emphasized his continued commitment to the peace process and the establishment of a Palestinian state, insisting he was just as committed now as he was on his first day in the White House. He told Abbas that at his White House meeting with Netanyahu two weeks ago, the two discussed the peace process at length, including the progress of the Israeli-Palestinian talks held in Amman under Jordanian auspices.

He therefore urged Abbas not to incorporate a threat to dismantle the Palestinian Authority in the letter.

But Abbas responded that he intends to send Netanyahu the letter in the next few days. In it, he will blame Israel for the impasse in the peace process and stress that "the current situation cannot continue."

Abbas told Obama that the Palestinians are prepared to return to talks with Israel should it accede to the Quartet's demand that it present clear positions on borders and security. He also complained to Obama about the continuation of settlement construction in the West Bank, and about attacks by settlers against Palestinians.

A senior Palestinian official told Haaretz that following this discussion with Obama, the PA president is determined to deliver the ultimatum to Netanyahu in the next few days. A senior Israeli official who deals with Palestinian issues said it is unlikely that international pressure will prevent Abbas from sending the letter, but it might persuade him to soften his language and excise the threat of dismantling the PA.

Drafts of the Abbas letter that were leaked to the Palestinian media suggest he will say that the PA's establishment was intended as an interim stage, one which would allow the Palestinians to transition from occupation to political independence. But in reality, Abbas will complain, Israel has emptied the PA of all authority and turned it into a useless entity.