WASHINGTON -- Struggling to break decades of hostility, President Barack Obama convened a new round of Mideast peace talks Wednesday and told Israeli and Palestinian leaders they faced a fleeting chance to settle deep differences.
"This moment of opportunity may not soon come again," Obama said at the White House before hosting Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas in the first face-to-face peace talks in nearly two years. "They cannot afford to let it slip away."
Obama sought to temper expectations, noting that it had taken his administration this long just to get the two sides back to the bargaining table for talks aimed at creating a sovereign Palestinian state beside a secure Israel.
"The hard work is only beginning," Obama said, with Secretary of State Hillary Rodham Clinton and special Mideast peace envoy George Mitchell at his side. "Neither success nor failure is inevitable. But this much we know: If we do not make the attempt, then failure is guaranteed. If both sides do not commit to these talks in earnest, then long-standing conflict will only continue to fester and consume another generation, and this we simply cannot allow."
He made clear that the stakes are high.
"Too much blood has already been shed. Too many lives have already been lost. Too many hearts have already been broken," he said. "And despite what the cynics say, history teaches us that there is a different path. It is the path of resolve and determination, where compromise is possible and old conflicts at long last can end."
In a carefully arranged series of talks designed to lay the final groundwork for negotiations, Obama met separately with Netanyahu and Abbas as well as with Jordan's King Abdullah II and Egyptian President Hosni Mubarak. Later they all gathered for dinner, a private prelude to Thursday's scheduled start of formal negotiations at the State Department.
In his Rose Garden remarks, Obama noted that many are skeptical or opposed -- a view underlined by two days of Palestinian attacks on Israelis in the disputed West Bank.
"We are under no illusions," Obama said. "Passions run deep. Years of mistrust will not disappear overnight."
In earlier remarks after his meeting with Netanyahu, Obama assailed those responsible for the killings of four Israelis near the West Bank city of Hebron on Tuesday. The militant Hamas movement, which rejects Israel's right to exist and opposes peace talks, claimed responsibility.
Netanyahu said the killings were carried out by people who "trample human rights into the dust and butcher everything they oppose."
On Wednesday, Israeli police reported still another attack, saying Palestinian militants wounded two Israelis driving in the West Bank. Two people were reported injured, their car riddled with bullets.
Direct Israeli-Palestinian negotiations broke off nearly two years ago, in December 2008, and the Obama administration spent its first 20 months in office coaxing the two sides back to negotiations. Obama was adamant Wednesday that extremist violence would not derail the process.
"There are going to be extremists and rejectionists who, rather than seeking peace, are going to be seeking destruction," he said. "The United States is going to be unwavering in its support of Israel's security. And we are going to push back against these kinds of terrorist attacks. And so the message should go out to Hamas and everyone else who is taking credit for these heinous crimes that this is not going to stop us."
Expectations for the Washington talks are low, yet the consequences of failure are high. The Israeli-Palestinian conflict is a constant source of grievance and unrest in the Muslim world. The failure of past peace efforts has left both sides with rigid demands and public ambivalence about the value of a negotiated settlement.
Under a so-called two-state solution to the Israeli-Palestinian conflict, the West Bank is supposed to make up the bulk of an independent Palestinian state alongside Israel, with precise borders to be drawn at the peace table. Expansion of Jewish housing makes those borders ever more complicated.
Beyond the settlements, Israel and the Palestinians face numerous hurdles in resolving other contentious issues, notably the borders of a future Palestinian state, the political status of Jerusalem and the fate of Palestinian refugees.
Also complicating the outlook are internal Palestinian divisions that have led to a split between Abbas' West Bank-based administration and Hamas, which is in control of Gaza. Hamas is not part of the negotiations and has asserted that talks will be futile.
In a statement to be delivered before Wednesday's White House dinner, Netanyahu framed Israel's ambitions for the peace process.
"Our goal is to forge a secure and durable peace between Israel and the Palestinians," he said, according to an advance copy of his remarks. "We do not seek an interlude between two wars. We do not seek a temporary respite between outbursts of terror."
Netanyahu stressed the central importance of security assurances for the Jewish state as part of any land-for-peace agreement with the Palestinians.
"We left Lebanon, we got terror. We left Gaza, we got terror. We want to ensure that territory we concede will not be turned into a third Iranian-sponsored terror enclave aimed at the heart of Israel," Netanyahu said.
Associated Press writers Matthew Lee, Matti Friedman, Abed Arnaout, Ben Feller, Darlene Superville and Julie Pace contributed to this report.