JERUSALEM — The Obama administration's ambassador to the United Nations told Israelis on Wednesday that it is not enough just to pay "lip service" to peace and urged the government to immediately relaunch negotiations, without preconditions, aimed at creating an independent Palestinian state.

Ambassador Susan Rice, in an address at a high-powered conference hosted by Israeli President Shimon Peres, assured Israelis — many of whom are wary of Obama's Mideast agenda — that her government is committed to their security.

"As President Peres always reminds us, being serious about peace means taking risks for peace," Rice said. "Being serious about peace means understanding that tomorrow need not look like yesterday."

Peres shared the 1994 Nobel Peace Prize with Palestinian leader Yasser Arafat and slain Israeli leader Yitzhak Rabin for Mideast peace efforts.

President Barack Obama has been attempting to restart talks between Israelis and Palestinians since taking office. The Palestinians have refused to resume negotiations, demanding that Israel first stop building settlements on war-captured lands they want for their future state.

Israeli Prime Minister Benjamin Netanyahu says he is ready to start talking, but has laid out a hard-line agenda that has made the Palestinians suspicious of his intentions. Netanyahu says he will never share control of Jerusalem — a key Palestinian demand — and has given no indication of whether he is prepared to cede large areas of captured land claimed by the Palestinians.

Earlier, Rice met Netanyahu and she is scheduled to meet Palestinian Prime Minister Salam Fayyad on Thursday.

Rice's speech on Wednesday appeared aimed at both sides, urging them to plunge headlong into talks that would address all major issues, including Jerusalem.

"We must all decide whether we are serious about peace or whether we will lend it only lip service," she said.

Her address reflected Obama's emphasis on seeking diplomatic solutions to the world's troubles. Obama's vision, and his outreach to the Muslim world, have many Israelis worried that the U.S. president will depart the near-unconditional support for the Jewish state his predecessors had.

Addressing these concerns, Rice said the U.S. "remains fully and firmly committed to the peace and security" of Israel.

At the same time, she urged the world's leaders to rise above narrow interests and work for the greater good of peace.

"We know what is holding us back: short-term, shortsighted definitions of self-interest," she said. "Treading water above powerful undertows will only leave us driven farther and farther from shore."

"So we must choose: to continue business as usual in a vain attempt to withstand the whirlwind, or to work together to seize this rare chance for deep and lasting change — change driven by transformational leadership ... and supported by visionary citizens and publics who understand our mission and our moment," she added.