US president Barack Obama and Israeli prime minister Binyamin Netanyahu will meet in Washington on Monday for a discussion that could help to subdue - or amplify - the growing calls for war with Iran.
The last meeting between the two leaders, in September, focused largely on the prospects for new Middle East negotiations between Israel and the Palestinians, coming day after Obama promised to veto a Palestinian bid for full recognition at the United Nations.
But aides say Monday's meeting will be dominated by Iran, as Netanyahu pushes the US government to take a more aggressive stance on Tehran's nuclear programme. There has been widespread speculation, in the press and in public statements by Israeli officials, that Israel could attack Iran this summer.
The Obama administration has not said whether it would support such a move, and in recent weeks has said it sees no evidence that Iran is building a nuclear weapon.
Their meeting comes against the backdrop of the annual conference of the American Israel Public Affairs Committee (AIPAC), the powerful pro-Israeli lobbying group whose members will fan out across Capitol Hill this week to pressure legislators in the leadup to this year's elections.
No 'policy of containment'
In an address to the AIPAC conference on Sunday night, Obama called for Israel to allow time for sanctions against Iran to work, but promised to leave "all options on the table" regarding Iran's nuclear programme.
"Iran's leaders should understand that I do not have a policy of containment," he said. "I have a policy to prevent Iran from obtaining a nuclear weapon."
Netanyahu's government, and AIPAC's leadership, wanted Obama to go further. The Israeli prime minister wants Obama to lay down "red lines" - a clear statement of when the United States would attack Iran over its nuclear programme. Netanyahu is scheduled to deliver his own speech to the AIPAC conference on Monday night.
AIPAC, meanwhile, is circulating flyers which describe an Iran with even the capability to build nuclear weapons as "unacceptable."
Any country with a well-developed peaceful nuclear programme has a degree of "breakout capacity," the ability to quickly build a nuclear device. AIPAC's position, which is shared by many in Netanyahu's inner circle, would call for a strike on Iran once its nuclear programme reached a certain point, even if the Iranian leadership was not actively building a nuclear weapon.
James Clapper, the US director of national intelligence, testified before Congress in January that he believed Iran had not yet decided whether or not to build a bomb.
International negotiations over Iran's nuclear programme have been stalled for more than a year, but the Iranian government abruptly announced last month that it would be willing to resume talks without any preconditions.
Israeli officials want Iran to completely suspend its uranium enrichment programme before the West resumes negotiations. But the White House has apparently rejected that demand, which Iran would almost certainly refuse; Obama told AIPAC he still believed a diplomatic solution was possible.
The Obama-Netanyahu meeting has been the subject of intense speculation in the Israeli and American press. Yediot Aharonot called it "Netanyahu's moment of truth," forcing the Israeli prime minister to decide whether to support Obama or "collide" with him. The Jerusalem Post likened the two world leaders to courting teenagers, "sending messages to each other through emissaries before their big rendezvous."
Gideon Levy, a columnist for the liberal newspaper Ha'aretz, argued that Netanyahu's aggressive lobbying on Iran could eventually undercut US support for Israel.
"Netanyahu's Israel has dictated the global agenda as no small state has ever done before, just as its international standing is at its nadir and its dependence on the United States at a zenith," he wrote.
Obama sought to tone down some of that speculation during his AIPAC speech; Netanyahu, too, has reportedly instructed his aides to stop talking to the press about Iran.
"Already there is too much loose talk of war," Obama said. "For the sake of Israel's security, America's security, and the peace and security of the world, now is not the time for bluster."
The Iranian nuclear programme has also become an election-year issue in the United States, where all of the Republican presidential candidates have been sharply critical of Obama's approach to Iran.
Former Massachusetts governor Mitt Romney, the front-runner in the Republican primary race, told an audience shortly after the president's speech that "if Barack Obama is re-elected, Iran will have a nuclear weapon."
Three of the Republican candidates - Romney, Newt Gingrich and Rick Santorum - will address the AIPAC conference on Tuesday.