Chief Israeli negotiator Tzipi Livni and Palestinian Authority President Mahmoud Abbas met briefly in London on Thursday night, in the first meeting between Israeli and Palestinian officials since peace talks failed last month, Channel 2 reported.According to the report, Livni expressed to Abbas Israel's disapproval of his decision to form a unity government with Hamas.Channel 2 quoted unnamed sources as saying that Prime Minister Binyamin Netanyahu was angry at Livni for holding the unsanctioned meeting.American officials confirmed the meeting between the two and emphasized that the rendezvous was not planned in advance, according to Channel 2.Both Livni and Abbas were in London for separate meetings with US Secretary of State John Kerry, who was in town for talks on Syria.Livni was given special immunity to enable her to address a JNF meeting this week, marking her first visit to the United Kingdom since 2009, when pro-Palestinian supporters and their allies, shortly after the Gaza war, threatened to have her arrested for alleged war crimes against the Palestinians.She also met with Foreign Secretary William Hague to brief him on the stalled peace talks.Abbas met with Kerry earlier in the week, hoping to persuade the US administration to accept a Palestinian unity government.Abbas planned to make it clear to Kerry that the proposed government would recognize Israel and reject violence, a senior Palestinian official in Ramallah said.Herb Keinon, Khaled Abu Toameh and Jerry Lewis contributed to this report.