JERUSALEM—Secretary of State Hillary Clinton sought on Monday to reassure Israel that U.S. efforts to block Iran´s nuclear ambitions are working, but said the Obama administration´s strategy of diplomacy and economic sanctions needs more time to play out.

After a day of meetings with Prime Minister Benjamin Netanyahu and other Israeli leaders, Mrs. Clinton told reporters that recently imposed economic sanctions are putting unprecedented pressure on Tehran. She acknowledged that Iran has responded with "nonstarters" to several rounds of negotiations with international powers and that Iranian leaders hadn´t made a "strategic decision" to engage in talks. She said Israel and the U.S. are in close coordination on Iran.

"Our two-track policy of diplomacy and pressure is in full move here," she said following a dinner meeting at Mr. Netanyahu´s official residence in Jerusalem. "I´m not going to prejudge the outcome of these efforts. I think that its absolutely fair to say [the U.S. and Israel] are on the same page at this moment trying to figure our way forward to have the maximum impact on affecting the decisions that Iran makes."

Her meetings with Israeli officials were part of a recent effort by the Obama administration—which sent National Security Adviser Tom Donilon here last week and will dispatch Defense Secretary Leon Panetta later this month—to keep in close coordination with Israel.

The stalling of the so-called P5+1 talks with Iran, which include the U.S., the U.K., France, China, Russia and Germany, has kicked up speculation that Israel may decide to make a pre-emptive strike on Iran in the coming months—a move that would risk a regional war and a spike in oil prices amid an American election campaign.

Mr. Netanyahu and Defense Minister Ehud Barak have warned repeatedly that Iran is using the talks as a tactic to buy time before it can build a nuclear weapon, and they have said Israel believes time is running out before military action is required.

Iran says its nuclear program is solely for peaceful purposes.

Israeli officials said the American visits have focused on reassuring Mr. Netanyahu´s government that President Barack Obama is committed to denying Iran nuclear-weapons capability. "The message has been: We´re going to handle this," said an Israeli official briefed on Mrs. Clinton´s trip.

Mrs. Clinton met with Mr. Barak, Israeli President Shimon Peres, and Foreign Minister Avigdor Lieberman. She also met in Jerusalem with Palestinian Prime Minister Salam Fayyad.

Israeli officials said they were especially eager to hear Mrs. Clinton´s impressions of Egypt following her weekend visit there. Israel is worried about the fate of its ties with Egypt, and by past comments from Egyptian President Mohammed Morsi about revisiting the 33-year-old Egypt-Israel peace treaty.

Over the weekend, she urged Egypt´s military and its Islamist- dominated political leadership to seek cooperation rather than confrontation. Mrs. Clinton said she asked Cairo to do its utmost to preserve its peace treaty with Israel.

Mrs. Clinton told reporters in Jerusalem that the Egyptian political system is a "work in progress" and the economic, social and political challenges would be "daunting for the most experienced political leaders."

Asked to comment on protesters who threw tomatoes at her motorcade, she said she wasn´t offended and that it reflected increasing freedom of expression in the country. She added, however, that it also indicated anxiety among Egyptians about what "may or may not be happening" regarding a new Parliament and a new government.

"The sooner there can be a government that takes responsibility whose actions can be judged and held accountable, then people will be able to draw decisions, because words don´t mean as much as actions," she said. "So therefore I was not offended. I was relieved that nobody was hurt and I felt bad that tomatoes were wasted." —Jay Solomon contributed to this article. (Copyright © Dow Jones & Company, Inc.) 07/17/12)