President Bush, on the first trip of his presidency to Israel, is trying to build momentum for stalled Mideast peace talks and clear up confusion about whether the United States is serious about confronting Iran about its suspected nuclear ambitions.

He was to arrive in Israel on Wednesday for talks with Prime Minister Ehud Olmert and other leaders.

Bush’s challenge is to convince skeptical governments that, with just a year remaining in his presidency and Americans deep in the process of selecting his successor, he is willing to devote the time and effort necessary to bridge decades of differences in this troubled region.

Expectations of success are low, and no one is predicting big breakthroughs as Bush visits Israel, the Palestinian-governed West Bank, Kuwait, Bahrain, United Arab Emirates, Saudi Arabia and Egypt.

Israel was putting the final touches on the preparations for the Bush visit, deploying about 10,000 police in Jerusalem, employing garbage collectors overtime in the holy city and rolling out red carpets at the airport.

There’s been little headway since Bush hosted a splashy Mideast conference in November in Annapolis, Md., and launched the first major peace talks in seven years.

On the eve of Bush’s arrival, Olmert and Palestinian President Mahmoud Abbas pledged to have negotiators begin work immediately on the so-called final status issues. These include the final borders between Israel and a future Palestine, completing claims to the holy city of Jerusalem, the fate of millions of Palestinian refugees and Israeli security concerns.

The Palestinians are angry about Israeli plans to build new housing in east Jerusalem and the West Bank _ areas captured by Israel in the 1967 Mideast war and claimed by the Palestinians for their future state.

Israel, for its part, has demanded that Palestinian forces do more to rein in militants in the West Bank. Since Olmert and Abbas last met, two Israelis were killed in the West Bank, and Israeli security forces say members of Abbas’ Fatah movement were responsible.

Secretary of State Condoleezza Rice, who will be accompanying Bush, called Tuesday for the Israelis and the Palestinians to move quickly.

“We do expect both sides to act with urgency. We do expect the negotiations to move forward. We do expect both sides to live up to their obligations,” she said in an interview with Israel’s Channel 10 TV. “The Palestinians need to do everything they can to fight terror. Israel, frankly, needs to look at its road map obligations and to do nothing that would prejudge the final status agreement.”

The U.S.-backed “road map” peace plan requires Israel to freeze settlement construction and the Palestinians to crack down on militants.

Bush’s aim is to nurture an agreement over the next 12 months between Israeli and Palestinian leaders.

“They need to have a vision that’s clearly defined, that competes with the terrorists and the killers who murder the innocent people to stop the advance of democracy,” Bush said at the White House on Tuesday before beginning his trip.

Bush, in pre-trip interviews, acknowledged he will have to explain a new U.S. intelligence report that concluded _ contrary to earlier White House assertions _ that Iran stopped its nuclear weapons program in 2003. That finding undercut U.S. efforts to build support for sanctions against Iran and raised questions about whether the White House was losing its interest in confronting Iran.

Bush says the report proved that Iran was a threat and is a threat. He says Iran is still enriching uranium and could restart its weapons program.

Bush said a confrontation in which Iranian boats threatened to blow up U.S. Navy vessels in the Strait of Hormuz on Sunday was a “provocative act.”

“It is a dangerous situation,” he said. “They should not have done it, pure and simple. ... I don’t know what their thinking was, but I’m telling you what my thinking was. I think it was a provocative act.”