RAMALLAH, West Bank (Reuters) - said on Tuesday there was a new "moment of opportunity" in the Middle East but cautioned in his first visit as an international envoy against expecting any peace breakthrough soon.
The Quartet of peace brokers -- the United States,, and -- has asked the British former prime minister to present in September an initial plan for building ruling institutions for a future Palestinian state.
Blair, in his first public remarks since starting his mission on Monday, said he came "to listen and to learn and to reflect" in preliminary talks with Israeli and Palestinian leaders.
"I think there is a sense of possibility at the moment. I think this is a moment of opportunity," he told reporters after meeting Palestinian Prime Minister Salam Fayyad, who said Blair was "uniquely positioned to help us move forward."
Earlier, in remarks after talks with Israeli President, Blair said translating possibilities "into something" would require work and thought "over time."
Blair also met, whose secular Fatah faction lost control of Gaza to Islamists in fighting last month, a development that has led and the West to redouble their efforts to bolster the moderate leader.
Blair ends his day with a private meeting with Israeli Prime Minister Ehud Olmert on Tuesday before flying out on Wednesday.
Diplomats say Blair's limited mandate could expand later into a more direct peacemaking role, an idea backed by Abbas's aides. Many Israeli officials are cool to the prospect.
"The mandate of Prime Minister Blair is motivated and generated by the objectives and not by the verbal mandate that he's given," said Abbas aide Saeb Erekat, in an apparent allusion to the goals of peace and Palestinian statehood.
Peres, a Nobel Peace laureate, hinted at a political mandate for the 54-year-old Blair, credited with successful peacemaking in Northern Ireland during his decade in charge in.
"He has on the one hand to see what can be done to advance the political matter and the economic affairs and to permit the Palestinians to build political institutions," said Peres, whose post is largely ceremonial.
Peres, 83, said Blair faced "one of the most responsible and demanding tasks of his career" and there was "a real chance for his success."
"I think there is a serious window of opportunity to advance peace," Peres said. "I don't know the duration of this opportunity. I'm afraid it's not too long."
Hamas, which has spurned international demands to recognize Israel, renounce violence and accept interim peace agreements, has said Blair must deal with the Islamic movement and avoid "double standards." Blair shunned the group during the visit.
Nabil Abu Rdainah, another Abbas aide, said the Palestinians hoped to take advantage of Blair's personal relationship with U.S. and Israeli leaders.
"If that is going to help our political horizon, that would be good," Abu Rdainah said.
Blair was due to wrap up the visit to Israel and the West Bank on Wednesday and then travel toand the . He plans to return to the region for the first half of September, before a Quartet meeting followed by a Middle East conference organized by U.S. .
(Additional reporting by Adam Entous, Jeffrey Heller and Allyn Fisher-Ilan in; Wafa Amr in )