Washington's envoy to the Middle East continued his shuttle mediation between leaders in the region Friday, meeting Palestinian President Mahmoud Abbas in Ramallah, DPA reported.
George Mitchell made the short motor journey from Jerusalem to the central West Bank city after talks on Thursday with Israeli officials, including Prime Minister Benjamin Netanyahu.
The latest round of mediation is being held in a pessimistic atmosphere.
US President Barack Obama, in an interview with Time Magazine, conceded he "overestimated" his administration's ability to persuade Israelis and Palestinians to return to the negotiating table.
The negotiations were broken off more than one year ago, as Israel headed into new elections which saw Netanyahu's hardline Likud party return to power.
"Both sides - the Israelis and the Palestinians - have found that the political environment, the nature of their coalitions or the divisions within their societies, were such that it was very hard for them to start engaging in a meaningful conversation," said Obama. "I think that we overestimated our ability to persuade them to do so when their politics ran contrary to that."
Obama said Abbas had the radical Islamist Hamas, which controls Gaza, looking over his shoulder, while Israel too "still found it very hard to move with any bold gestures."
He was referring to Netanyahu's move to freeze construction in Israel's West Banks settlements for 10 months. The move has sparked outrage among the premier's nationalist electorate, but it has been rejected by the Palestinians as insufficient because it excludes East Jerusalem.
The moratorium also excludes public buildings in West Bank settlements, as well as several thousand apartments whose construction had already begun.
Abbas has said he will not sit down with the Netanyahu government unless it implements a full settlement freeze.
"I think it is absolutely true that what we did this year didn't produce the kind of breakthrough that we wanted," Obama told Time Thursday. "If we had anticipated some of these political problems on both sides earlier, we might not have raised expectations as high."
Meeting Israeli President Shimon Peres in Jerusalem, Mitchell nonetheless said that despite "the complexities and difficulties outstanding, we will pursue until we achieve that objective" of a comprehensive Middle East peace.
"In spite of all the declarations and the mood we have to move ahead with no alternative. It's so demanding and so complicated but we don't have a choice, all of us," said also Peres.