WASHINGTON — With President Bush staving off Democratic challenges to the war in Iraq, some congressional leaders are looking to challenge Mr. Bush’s foreign policy on another front, focusing on Secretary of State Rice’s recent attempts to resume negotiations between Israel and a fractured Palestinian Authority.

Today the House subcommittee that oversees diplomacy and foreign policy in the Middle East will hear from senior State Department officials on the status of American aid to the Palestinian Arabs and about international banking sanctions that have left the Hamas-controlled Palestinian Authority cash-strapped.

The chairman of that congressional panel, Rep. Gary Ackerman, a Democrat of New York, told The New York Sun yesterday that he intends to make sure that Ms. Rice does not undermine the financial embargo of the Hamas-controlled regime in Gaza. He said he would inquire about recent American assurances to European and Arab banks that they will not be barred from American markets for sending money to the Palestine Liberation Organization.

Earlier this year, Mr. Ackerman and other colleagues persuaded the House leadership to drop language from an Iraq war funding bill that would have barred the president from taking any action against Iran without congressional approval. Now, the New York lawmaker says he has support from other key committee chairmen for keeping the embargo on the Palestinian Authority in place. Hamas, whose charter calls for Israel’s destruction, is on the State Department’s terrorist list. Since Hamas-supported candidates won Palestinian legislative elections in January 2006, America and Europe have cut back on aid to the Palestinian Authority out of concern that the funds would aid the terrorist group.

“If the process is more porous than we conceived it to be, if there is money funneled into hands to which it is not intended, we will look to close that all off,” he said. “We will use our leverage, our committee and other committees that would have jurisdiction over financial regulations, to push the process that would stop that and prevent that from happening,” he said.

The desire to keep pressure on Hamas is at odds with the advice issued in March by a billionaire hedge fund operator and donor to left-wing American causes, George Soros, who criticized the Bush administration for not demanding more rapid negotiations between Israel and the Palestinian Authority. The caution about diplomacy between Israel and the Palestinian Arabs also might be seen as out of step with the calls from Democrats for Secretary Rice to move forward with her engagement of Iran and Syria, two states the American military has said are sending terrorists and explosives to kill our soldiers in Iraq. This weekend, Ms. Rice will begin discussions with Iran’s foreign minister.

The question of America’s policy on the Hamas embargo emerged on May 10, when a spokesman for the American consulate in Jerusalem, Micaela Schweitzer-Bluhm, told Reuters, “Our banking regulations generally do not apply to the PLO account . . We are working with Salam Fayyad to clarify how entities might contribute to this account.” Mr. Fayyad is the American-educated finance minister in the new unity government for the Palestinian Authority.

Mr. Fayyad has urged the Treasury Department to help him assure foreign banks that they would not be penalized for contributing funds the PLO accounts, which could pay salaries that have gone unpaid for months for Palestinian bureaucrats and civil service workers.

The fear for Israel, however, is that those funds would create a way to circumvent the sanctions that restrict the cash flow for Hamas, which would in turn funnel the money for salaries to purchase rockets and pay terror cells.

A spokesman yesterday for the State Department’s bureau of near east affairs, David Foley, said, “We and our European and Arab partners believe that the Palestinian people should continue to receive international support via accountable and transparent mechanisms. Our existing regulations, restricting financial dealings with the Palestinian authority government have not changed and remain in place.”

But he added, “The department of the treasury’s Office of Financial Assets Control restrictions do not generally apply to the PLO, however if we are talking about the PLO economic office account it is subject to (these) restrictions. Transactions that do not involve US persons including U.S. financial institutions would not be subject to the jurisdiction of OFAC.”

Mr. Ackerman yesterday said he also intended to focus his questions on the potential for American aid money to support Hamas.

“You don’t negotiate with terrorists,” Mr. Ackerman said. “The Palestinians had a good thing going by electing President Abbas. He has historically been on the side of negotiations and denouncing violence, but he has gotten himself in bed through a unity government with these committed terrorists. We’re not going to negotiate with them. The Palestinians had a democratic election, that is true, but elections have consequences.”