(CBS News) A day before Quartet on the Middle East mediators are expected to meet in Washington, D.C., the Palestine U.N. Observer, Ambassador Riyad Mansour, spoke with CBS News about prospects for peace. For 65 years, negotiations to bring peace to the Middle East have failed. This week, the Quartet principals -- U.S. Secretary of State Hillary Clinton, U.N. Secretary-General Ban Ki-moon, European Union foreign policy chief Catherine Ashton and Russian Foreign Minister Sergey Lavrov -- are scheduled to meet at Blair House in Washington, after having called for a resumption of Israeli-Palestinian talks and for a framework agreement by the end of 2012.
The previous Quartet summit took place last September at U.N. headquarters at the same time that Mahmoud Abbas, the Palestinian president, submitted an application for full Palestinian membership - a plan which later failed at the Security Council.
"The talks are stalled," said Mansour, "We hope that the Quartet can succeed in getting the negotiations out of the impasse that we are going through."
But Israel and Palestine appear to remain far apart. In an article in the Los Angeles Times on Tuesday, writer Edmund Sanders in Jerusalem said: "Israel's government is scrambling to find ways to save some of the unauthorized West Bank settlements it once promised to dismantle, including some that are built partly on private Palestinian land."
Mansour, who was present when Abbas presented the failed U.N. membership bid, said that if the parties want to establish a two-state solution, they must both comply with the Quartet mandate.
Mansour said, "The Israeli side, they say that they want to have a state for the Jewish people, which is Israel, in which the majority are Jews. If you keep pushing the envelope to take the land of the Palestinian state in the West Bank and Gaza and East Jerusalem, and build more settlements and have more settlers, then this action is destroying the two-state solution."
Thus, the Quartet, meeting tomorrow, knows that delaying until after the U.S. election - what some analysts believe is happening - could have long-term effects.
"If they destroy the two-state solution, then they are pushing in the direction of a one state solution. What is the one state solution? That the two people, the Palestinian people and the Israelis, the Jews in Israel, would live in one state, in which the population is roughly the same. In a few years, the Palestinians will be more than the Jews in that one state. Therefore, the dream of the Zionists of having a state for the Jews will diminish," Mansour added.
And, if talks fail, Palestinian President Mahmoud Abbas said this week, Palestine will return to the U.N., this time to the General Assembly for enhanced status as an "observer state."
Israel's U.N. Ambassador, Ron Prosor, considered one of Israel's most experienced diplomats,about the implications of a Palestinian bid for statehood at the United Nations and the threats to peace in the Middle East.
Violence in the region has increased in recent months. Israel said Palestinian militants had fired a total of 180 rockets from Gaza since the violence erupted, leaving four Israelis wounded. Israel's Air Force responded and called on the U.N. Security Council to take action over the rocket assault. Prosor wrote to the U.N. that the Gaza Strip, ruled by Hamas, continues to be a bastion for terrorist activity, adding that over a hundred rockets were fired against Israel.
Palestinian Authority Prime Minister Salam Fayyad called on the Quartet on the Middle East to speak out more forcibly on the issue of Israeli violence against Palestinians when it meets Wednesday in Washington.
In January, the U.N. Secretary General traveled to Amman, Jerusalem, Ramallah, Gaza and Tel Aviv, which was an attempt to restart Jordan's direct talks between the Israelis and Palestinians - but that effort has also stalled and the conflict has become overshadowed by the uprising in neighboring Syria.Watch Pamela Falk's video from the Secretary General's Mideast trip
Still, Mansour believes that the 65-year-old conflict can arrive at a solution, "if both sides negotiate in good faith," a difficult objective in a war-torn region.