The day after Barack Obama claimed victory in the Democratic primary race, he went before the American Israel Public Affairs Committee to forcefully declare his support for Israel, argue for strong diplomacy in the Middle East, and criticize rival John McCain for supporting a "plan for staying, not a plan for victory" in Iraq.

The U.S.-led Iraq war has allowed Iran to build its influence, "and the United States and Israel are less secure," he said. Condemning its leader for denying the Holocaust, threatening Israel, trying to attain nuclear weapons and arm Hamas and other organizations, Obama said, "Israel's security is sacrosanct. It is nonnegotiable."

Obama also said that Hamas and Hezbollah must renounce terrorism and recognize Israel's right to exist before the United States would consider engaging with them in diplomacy. He added that such negotiations would only take place at a time and location chosen by the United States, and would only go forward if the negotiations served U.S. foreign policy goals.

McCain spoke to AIPAC last week and accused Obama of offering to meet with U.S. enemies in the Middle East without such preconditions.

"Rather than sitting down unconditionally with the Iranian president or supreme leader in the hope that we can talk sense into them, we must create the real-world pressures that will peacefully but decisively change the path they are on," McCain said.

Officials from the United States and Israel said Tuesday the rest of the world isn't doing enough to stop Iran from developing nuclear weapons and accused Iran of continuing a covert drive for the weapons, although U.S. intelligence has said Tehran quit its active warhead program years ago.

Secretary of State Condoleezza Rice and Israel's embattled leader, Prime Minister Ehud Olmert, both used speeches to a pro-Israel lobbying group to complain that European and other nations are undermining the hard line against Iran's nuclear program by pursuing business relationships with Tehran.

"Our partners in Europe and beyond need to exploit Iran's vulnerabilities more vigorously and impose greater costs on the regime - economically, financially, politically and diplomatically," Rice said.

Olmert went further, saying in a speech to the American Israel Public Affairs Committee that other countries should penalize Iran by barring business travelers, blocking financial transactions and imposing sanctions on Iran's import of refined gasoline and on countries that perform that task for oil-rich but facilities-poor Iran.

"Each and every country must understand that the long-term cost of a nuclear Iran greatly outweighs the short-term benefits of doing business with Iran," Olmert said.