WASHINGTON - Israeli Defense Minister Ehud Barak will lobby the United States on Tuesday to rethink its demand to curb West Bank settlement growth, a dispute that has strained ties as the allies try to close ranks against Iran.

A U.S.-sponsored 2003 peace road map obligates Israel to stop settlement activity on occupied land Palestinians see as part of their future state and that the World Court deems illegal. The Obama administration has pushed Israel to halt such moves.

But Israel says the previous Bush administration tacitly agreed that new homes could go up to match settler population growth.

Israel's right-wing prime minister, Benjamin Netanyahu, on Monday said a total settlement freeze would not be reasonable -- risking a diplomatic showdown with Western powers keen to revive Palestine talks and stabilize the wider Middle East.

An Israeli official said Barak, whose responsibilities include overseeing the West Bank, would argue for greater American flexibility on settlements when he met National Security Adviser James Jones on Tuesday.

We're not happy with the American remarks (about the settlements), and Barak has his work cut out for him. His visit is part of a long process of trying to manage this dispute, the Israeli official said.

He said Barak would present the view that stopping private construction in areas where Israel claims sovereignty would be harmful to the Netanyahu government's domestic standing, not least given the unclear horizon on the Palestinian front.

In a letter in 2004 to then-Prime Minister Ariel Sharon, George W. Bush gave what Israel took as a presidential nod to its stated plan to annex major settlement blocs under any peace deal -- something Palestinians have ruled out as a non-starter.

PALESTINIAN CRACKDOWN

Palestinian President Mahmoud Abbas has made efforts to meet his own road map requirement of reining in anti-Israel militias. But his is a divided polity, with rival Hamas Islamists ruling the Gaza Strip and refusing to coexist with the Jewish state.

Jones has championed projects to boost Abbas's security forces and the West Bank economy, hoping to provide Palestinians an attractive alternative to Hamas, whose Gaza fiefdom has been further impoverished by an international embargo.

Netanyahu, however, has balked at giving Abbas powers that could be parlayed into sovereign rights, such as setting up an army. Israel fears that Hamas, having swept a 2006 election, might eventually expand its power base to the West Bank.

Underscoring this concern is the ascendancy of Iran, which backs Hamas and whose nuclear program Israel -- assumed to have the Middle East's only atomic arsenal -- considers a mortal threat.

For now, Israel has quietly acceded to U.S. President Barack Obama's strategy of talking to Tehran about curtailing its uranium enrichment, a process with bomb-making potential. The Iranians say the program is for peaceful energy development.

Helping allay Israeli anxieties is a multi-level missile shield helmed by Barak and underwritten by the United States.

Israeli officials said Barak hoped to lay to rest a disagreement over whether the top tier should be Arrow III, an interceptor favored by Israel that would be produced jointly by Israelis and Americans, or a land version of a U.S. system known as Aegis, which some in Washington are pushing.

A seaborne Aegis is already stationed in the Mediterranean and a U.S. official said that Defense Secretary Robert Gates, who meets Barak on Thursday, could offer to ship it to Israel's shores should there be a flareup with Iran.

Barak, Israel's most decorated soldier, heads the center-left Labour party and is remembered in Washington as both warrior and peacemaker. In 2000, during President Bill Clinton's administration, he led short-lived negotiations with the Palestinians and Syria.

Israel George W. Bush