Ten days after harshly rebuking the Israeli government for a new housing plan in Jerusalem, Secretary of State Hillary Rodham Clinton said Monday that the Obama administration would push back “unequivocally” when it disagreed with Israeli policies, but that America’s support for Israel was “rock solid, unwavering, enduring, and forever.”

In a speech to a pro-Israeli group that mixed reassuring notes about helping Israel face the Iranian nuclear threat with a blunt warning that the status quo in the Middle East was “unsustainable,” Mrs. Clinton said, “There must be no gap between the United States and Israel on security.”

She defended the administration’s decision to criticize the government of Prime Minister Benjamin Netanyahu over its announcement of housing units for Jews in East Jerusalem during a visit to Israel by Vice President Joseph R. Biden Jr. The move, she said, undermined indirect talks that the administration is trying to broker between Israelis and Palestinians.

“Our credibility in this process depends in part on our willingness to praise both sides when they are courageous, and when we don’t agree, to say so, and say so unequivocally,” she said.

Still, Mrs. Clinton suggested that the spat with Israel might be nearing an end, with Mr. Netanyahu scheduled to meet with her here on Monday and with President Obama on Tuesday. Mr. Netanyahu, she said, offered “specific actions” in response to demands she made after the housing flap, which overshadowed Mr. Biden’s trip.

The administration is seeking additional gestures from Mr. Netanyahu, she said. But, she added, “We are making progress and we are working hard to keep the proximity talks moving ahead.”

After a week in which some worried that Israel and the United States were on the brink of a breakdown in relations, Mrs. Clinton’s speech to the American Israel Public Affairs Committee was clearly designed to calm the waters. Despite predictions that she would be booed, the crowd of 7,000 at the Washington convention center interrupted her repeatedly with standing ovations.

In an emphatic, spirited address that she could have delivered on the campaign trail, Mrs. Clinton said the United States would not tolerate a nuclear-armed Iran, which Israel views as a threat to its existence, and she vowed to impose tough new sanctions against the Iranian government.

“Our aim is not incremental sanctions, but sanctions that will bite,” she said.

Marshaling support for these sanctions at the United Nations was taking time, Mrs. Clinton said. “But we will not compromise our commitment to preventing Iran from acquiring these nuclear weapons.”

Mrs. Clinton praised Mr. Netanyahu for his endorsement of a two-state solution. She said the United States would not impose its own plan for a peace agreement on the Israelis or Palestinians, noting that the status of Jerusalem is a sensitive issue that would be hashed out at the bargaining table.

And Mrs. Clinton condemned those who incite violence against Israelis, whether it is a Hamas-controlled city renaming a square after a terrorist who killed Israelis, or Palestinians whipping up anger after Israel rededicated a synagogue in the Jewish quarter of Jerusalem’s old city.

But Mrs. Clinton also made it clear that the row over Mr. Biden’s visit might not be an isolated incident. The Obama administration, she said, would continue to speak out against decisions that it views as jeopardizing the peace process. “This was not about wounded pride,” she said.

“As Israel’s friend,” Mrs. Clinton said, “it is our responsibility to give credit when it is due and to tell the truth when it is needed.” NYT