US Secretary of State John Kerry met Palestinian president Mahmud Abbas in London, having earlier insisted that Israelis and Palestinians were determined to pursue direct peace talks.
Kerry met Abbas at London's Ritz Carlton on Sunday evening, the pair smiling and joking before holding a three-hour private meeting, their first talks since direct negotiations between the Israelis and the Palestinians began last month.
"They discussed the ongoing negotiations, how to intensify them, and how to ensure their success," said a State Department statement.
"The Secretary reiterated the importance of both sides taking steps to create an environment conducive to peacemaking and the ongoing commitment of the United States to playing an active facilitating role in the negotiations," it added.
Since becoming Secretary of State in February, Kerry has dedicated much of his energy to restarting peace talks between Israelis and Palestinians, which were frozen in September 2010.
After six trips to the region in four months, he met negotiators from both sides -- Palestinian Saeb Erekat and Israeli Justice Minister Tzipi Livni -- in Washington on July 29 and 30.
Secret bilateral meetings, with and without the presence of American sponsors, were then held in Jerusalem in August and early September.
During an earlier stop-off in Paris, Kerry said he soon planned to meet Israeli Prime Minister Benjamin Netanyahu. A State Department official however said it was premature to talk of trilateral talks between the three leaders.
Kerry had earlier praised efforts to hold talks "despite tough decisions and despite pressure that exists on both sides.
"Both the Palestinians and Israelis have remained steadfast in their commitment to continuing the talks," Kerry said in Paris after a meeting with Arab League officials.
On Wednesday, a senior Palestinian official dismissed Kerry's long-running efforts to broker peace, saying talks had been futile.
"Until now there has been no progress," the Palestine Liberation Organisation's Yasser Abed Rabbo told Voice of Palestine radio.
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But a State Department official on Sunday told the travelling press that the Palestinian official was "ignorant of what's happening in the negotiations".
"What they are saying is inaccurate and should not be taken as an indication of what actually happens in the negotiating room," he warned.
"It's unhelpful to the negotiations for these unnamed and in some cases named officials to be coming out and characterising things that they know nothing about."
Kerry also met in Paris with his Egyptian, Qatari and Saudi counterparts as part of efforts to engage the whole region in a solution.
"Something we learnt in a previous effort to resolve the Israeli-Palestinian conflict is if you don't have key Arab players in on the takeoff, you cannot expect them to be in on the landing," the US State Department official said.
"And we need them very much to be in on the landing of this effort...because their support and their anchoring of the agreement in an Arab base is going to be critical to the effort to ensure Palestinian support," he added.
During talks with Arab League officials, Kerry said there was agreement that "a final status agreement is important in enhancing regional security and stability throughout the Middle East".
Qatari Foreign Minister Khaled al-Attiyah however criticised Israel for continuing to build Jewish settlements, saying it was damaging peace efforts.
"What we noticed is that each time a round of negotiations is to start it's preceded by an announcement of settlements," he said.
This "directly affects the negotiations", Attiyah said.
In line with Kerry's desire to keep the details of the negotiations secret in order to give the process a chance to work, little has leaked about the talks.
Kerry also urged the European Union to suspend new guidelines introduced in July forbidding its 28 member states from dealing with or funding any Israeli "entities" in the occupied Palestinian territories, including the West Bank and east Jerusalem.