JERUSALEM (Reuters) - U.S. Secretary of State Hillary Clinton pledged on Tuesday to press hard for Palestinian statehood, putting Washington on a possible collision course with Israeli Prime Minister-designate Benjamin Netanyahu.

We happen to believe that moving toward a two-state solution is in Israel's best interests, Clinton told a news conference with Foreign Minister Tzipi Livni.

Netanyahu, whom Clinton was to meet later in the day, has spoken of Palestinian self-government but has shied away from saying he backed a U.S. and Palestinian vision of statehood that has been at the heart of Middle East peace talks.

Clinton, on her first visit to the region as secretary of state, said Washington believed the inevitability of working toward a two-state solution is inescapable. She promised the United States will be vigorously engaged in its pursuit.

At the news conference, Clinton also said two U.S. officials would be going to Syria for preliminary talks on improving relations between Washington and Damascus, which engaged Israel in indirect peace talks last year.

Asked about Iran's nuclear program and a possible U.S. dialogue with Tehran, Clinton said the United States will do everything necessary to ensure Israel's security and consult closely on the Iranian issue with Israeli leaders.

She said the United States shared Israel's concern about Iran's pursuit of nuclear weapons. Iran says its uranium enrichment program is aimed at generating electricity.

COALITION NEGOTIATIONS

Netanyahu, who clashed often with the U.S. administration when Bill Clinton, the secretary of state's husband, was in the White House, was tapped by Israeli President Shimon Peres after Israel's election last month to try to form a government.

He has enough parliamentary support to put together a right-wing government but has been seeking, unsuccessfully so far, to form a middle-of-the-road coalition that could reduce the chances of friction with the United States.

Netanyahu supports expansion of existing Jewish settlements in the occupied West Bank, a policy opposed by Washington and which Palestinians say could deny them a viable state.

President Barack Obama has said it will be a priority and Clinton pledged to push on many fronts early on.

The United States is Israel's chief ally. U.S. aid to Israel will amount to $2.55 billion in 2009.

Israeli-Palestinian peace talks, revived in late 2007, have stalled over violence, settlement-building and disputes over other core issues such as the future of Jerusalem and Palestinian refugees.

The Palestinian Authority suspended the negotiations after Israel launched in December a devastating 22-day offensive in the Gaza Strip with the declared aim of halting rocket attacks by militants in the Hamas-ruled enclave.

Clinton said a durable ceasefire in Gaza depended on Hamas stopping rocket fire at Israel.

In Egypt on Monday, she sought to show strong financial support for Palestinian President Mahmoud Abbas and pledged $900 million in U.S. aid, with a third going to help people in Gaza but the bulk aimed at boosting the Western-backed leader.

At the aid conference, Clinton was adamant no money would go to Hamas, saying it must recognize Israel, renounce violence and sign on to past Israeli-Palestinian agreements if it wanted to come out of isolation.

On Wednesday, Clinton visits the West Bank to see Abbas and Prime Minister Salam Fayyad.

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