Israel's Benjamin Netanyahu vowed to resist "pressures" as he arrived in Washington for talks with US President Barack Obama on the peace process and Iran's nuclear program.
When the two meet at the White House on Monday, their discussion will be crucial to determine whether Israel's negotiations with the Palestinians have a future beyond April 29, with US efforts focused on getting both sides to agree a framework for extending the talks.
But the rapidly-developing crisis in the Ukraine looked set to overshadow the visit, as Washington was mired in a tense showdown with Moscow after it dispatched troops to the region, in a development that pundits said could change the dynamics of Netanyahu's visit.
Speaking to reporters on the tarmac just before taking off for Washington, Netanyahu said he would discuss Iran and the peace process with Obama.
"I will insist on Israel's vital interests, first and foremost the security of its citizens. In recent years, the state of Israel has subjected to various pressures - we have rejected them. This is how it has been, and this is how it will be," he said.
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Although Netanyahu would like his meeting with Obama to deal predominantly with Iran, the White House has other ideas.
Last week, a senior official told The New York Times that Obama would press Netanyahu to "agree to a framework for a conclusive round of Israeli-Palestinian peace negotiations", being drafted by Secretary of State John Kerry.
When direct talks began in July 2013, the US diplomat had laid out a nine-month timetable to reach an agreement.
But there has been little progress and the aim now is to get the negotiators to agree on a framework for negotiating the core issues of the conflict, which would extend the deadline until the year's end.
