A day after announcing a new diplomatic initiative in the Middle East, Secretary of State Hillary Rodham Clinton traveled here Wednesday to show support for the Palestinian Authority, saying she had pressed the Israeli government to open border crossings to war-torn Gaza.

“We have obviously expressed concern about the border crossing,” Mrs. Clinton said after a meeting with the president of the Palestinian Authority, Mahmoud Abbas. “We want humanitarian aid to get into Gaza in sufficient amounts to help alleviate the suffering of the people in Gaza.”

Mrs. Clinton also spoke out against Israeli plans to demolish houses belonging to Palestinians in East Jerusalem. She said the orders, issued by the municipal authorities, were “unhelpful” to the peace process.

Israelis claim the houses were built illegally, while the Palestinian owners said they were unable to obtain building permits. Israel ordered the demolition of 88 homes last week, and another 55 this week. The dispute has become a microcosm of the larger battle over Jerusalem between Israelis and Palestinians.

“It is clearly a matter of deep concern to those who are directly affected,” Mrs. Clinton said.

Mrs. Clinton has used her brief, opening foray into Middle East diplomacy to signal a new direction, saying Tuesday that the Obama administration will send two senior officials to Syria this weekend to begin discussions with the government.

The overture suggests how the Obama administration intends to tackle three interlocking challenges in the Middle East: the nuclear threat posed by Iran; long-simmering tensions between Israel and Syria; and the grinding conflict between Israelis and Palestinians. Syria, regional experts say, could be the key to alleviating all three.

Visiting Ramallah after talks with Israeli officials in Jerusalem, Mrs. Clinton met the Palestinian prime minister, Salam Fayyad, and President Abbas before her scheduled departure from the region. Her remarks underscored the Obama administration’s continued rejection of Hamas, which controls the Gaza Strip and which many Western governments regard as a terrorist organization.

By seeking an understanding with Syria, which has cultivated close ties to Iran, the United States could increase the pressure on Iran to respond to its offer of direct talks. Such an understanding would also give Arab states and moderate Palestinians the political cover to negotiate with Israel. That, in turn, could increase the burden on Hamas, the Islamic militant group that controls Gaza, to relax its hostile stance toward Israel.

But in a region where even small steps take years to negotiate, officials sought to tamp down expectations of rapid progress. “It is a worthwhile effort to go and begin preliminary conversations,” Mrs. Clinton said, noting Syria’s wide influence in the region, as well as its troubled history with the United States. Yet, she cautioned, “we have no way to predict what the future of our relations with Syria might be.”

The State Department declined to elaborate on the issues the emissaries would broach in Syria or why negotiators were going now.

The two emissaries are Daniel B. Shapiro, a senior director at the National Security Council, and Jeffrey D. Feltman, the acting assistant secretary of state for Near Eastern affairs. Mr. Feltman, a former ambassador to Lebanon, has extensive experience with Syria; Mr. Shapiro advised the Obama campaign on the Arab-Israeli conflict.

Middle East experts say they believe that conditions for an opening to Syria are ripe on both sides.

“We’ve got a Syrian government that wants to engage,” said Martin S. Indyk, a former ambassador to Israel and a peace negotiator in the Clinton administration. “We’re likely to get an Israeli government that will find it easier to engage with Syria than with the Palestinians.”

There are clear benefits to Israel from better relations with Syria: the government of President Bashar al-Assad is a sponsor of Hezbollah, a militant group based in Lebanon, and provides a sanctuary for Hamas’s leaders in Damascus, Syria’s capital.

In May, Israel and Syria announced that they were in negotiations for a comprehensive peace treaty through Turkish mediators. Israel’s departing prime minister, Ehud Olmert, said he planned to brief Mrs. Clinton on those talks on Tuesday.

Benjamin Netanyahu, who is likely to become Israel’s next prime minister, will face pressure from the United States to move forward with the peace process. Mr. Indyk said that Mr. Netanyahu would find it more politically palatable to engage Syria than to alienate the settler movement by slowing or halting settlements as a concession to the Palestinians.

Nonetheless, Israeli public opinion polls show wide opposition to giving up the Golan Heights, captured by Israel in the 1967 war. In his previous stint as prime minister, Mr. Netanyahu initiated peace talks with Syria, but they came to nothing.

The Bush administration largely shunned Syria, recalling its ambassador in February 2005, after the assassination of a former Lebanese prime minister, Rafik Hariri. Many Lebanese accuse Syria of involvement in the assassination, a charge it denies. A United Nations tribunal has begun proceedings in the case.

While Mr. Feltman was the ambassador in Lebanon, three people were killed when a car bomb exploded next to an American Embassy vehicle in Beirut in January 2008. Suspicions again fell on Syria.

Mr. Feltman and Mr. Shapiro are accompanying Mrs. Clinton on her first tour of the Middle East as secretary of state, which began Monday in Egypt, where she said the United States would pursue peace “on many fronts.”

Meeting on Tuesday with Israel’s leaders during a time of political transition, Mrs. Clinton reaffirmed the desire of the United States for an agreement that would create a separate Palestinian state side by side with Israel.

But she was plainly reluctant to step into a domestic political tussle. Mr. Netanyahu, who is likely to form a right-wing government in the coming days, has emphasized economic development in the West Bank over negotiations to create a Palestinian state.

“We happen to believe that moving toward the two-state solution, step by step, is in Israel’s best interests,” Mrs. Clinton said. “But obviously, it is up to the people and the government of Israel to decide.”