Reporting from Washington and Jerusalem -- Key U.S. lawmakers whose support is crucial to the Obama administration's Middle East peace effort are showing signs of unease with the administration's aggressive approach to Israel.

Though they strongly support the peace initiative, many say they want the White House to back off its demand that the Israeli government halt all growth in Jewish settlements on Palestinian territory. Some members of Congress are also unhappy that the Obama administration has gone public in its dispute with Israel.

Rep. Gary L. Ackerman (D-N.Y.), chairman of the House foreign affairs subcommittee on the Middle East and South Asia, said focusing on settlement activity "detracts" from top U.S. goals in the region. However, he added: "I do not support a settlement freeze that calls on Israeli families not to grow, get married, or forces them to throw away their grandparents. Telling people not to have children is unthinkable and inhumane."

Rep. Anthony Weiner (D-N.Y.) told reporters Wednesday that "we have to be careful not to cross the line where it sounds like we are exerting overwhelming pressure . . . on our rather isolated ally."

Congress has always been a pivotal player on Mideast policy. When Presidents Carter and George H.W. Bush pressed Israel for concessions, Israeli leaders turned to their allies in Congress, who in turn brought pressure on the White House.

This year, the Democratic Congress has been strongly on the side of the popular new president's Middle East policy, and the Israeli leadership appears to be in a weaker position. When new Israeli Prime Minister Benjamin Netanyahu visited Washington last month, top lawmakers told him that rapid settlement growth was hurting Israel's cause, and urged him to slow it down, lawmakers said.

Yet ripples of concern are radiating through Congress and pro-Israeli organizations.

The disagreement seemed to sharpen in the last week, as President Obama called for a freeze on settlement growth. Israeli officials have complained that the administration was not recognizing secret oral agreements they say the George W. Bush administration reached with Israel to permit some expansion.

Palestinians and moderate Arab governments have made it clear that nothing short of a full freeze would satisfy them.

Though U.S. lawmakers and many advocacy groups continue to stand with Obama, there are hints that that position could shift.

The lawmakers "are feeling cross-pressured," said Steven J. Rosen, a former senior official of the American Israel Public Affairs Committee, the influential pro-Israel lobby. "Lots of Democrats have long wanted to see less settlement activity, so they're not inclined to intervene in a fight in defense of settlements. Yet there's no love for the theory that the United States should try to dictate to Israel its policies."

Last month, House Majority Leader Steny H. Hoyer (D-Md.) and Minority Whip Eric Cantor (R-Va.) collected 329 signatures on a letter that urged the administration to keep disagreements with Israel private, and to leave negotiations to the Israelis and Palestinians themselves.

Rep. Howard L. Berman (D-Valley Village), chairman of the House Foreign Affairs Committee, said the settlement question "is pretty much an isolated issue" and that the U.S. and Israel broadly agree on matters such as Iran's nuclear program and dealings with Palestinian militant groups.

He said the administration was justified in focusing on the settlements, since their growth puts in doubt for some Palestinians the possibility that they will ever have their own viable state. Even so, Berman said, he believes it is "not reasonable" to deny all settlement growth.

Israeli and U.S. officials continue seeking middle ground in almost daily conversations, yet the rift continues to grow.

Israeli officials say they have gone public on the secret oral deal during the Bush era to clear up the impression that Israel has "hoodwinked the world" on the settlements.

A senior Israeli official said Israel had followed the terms of the 2003 peace plan supported by the U.S. called the "road map" -- not appropriating new Palestinian land, not building new settlements, not providing new financial incentives for Israelis to move to the West Bank. But he said the deal permitted some "natural growth" in existing settlements.

"When Israel committed to the road map, it was based on private understandings," the official said. "It's hard for the United States to come and say, 'You have made these commitments,' but to ignore the understandings."

Elliott Abrams, a Bush administration official who took part in 2003 talks preceding the road map agreement, supported the Israeli arguments in an op-ed article that appeared April 8 in the Washington Post. He wrote that the Israelis had "largely adhered to guidelines that were discussed with the United States but never formally adopted" and aimed at permitting growth with only limited impact on Palestinians.