Both countries have accused Iran of secretly working toward building a nuclear weapon, and Netanyahu made it clear Wednesday after his talks with Obama that he believes the president is equally committed to preventing a nuclear-armed Iran.
In comments to reporters Wednesday and in Thursday's speech, Obama called for more diplomacy on Iran while endorsing Israel's right to defend itself as it sees fit. He also insisted that "all options" remain open -- code for a military strike to disable the Iranian program.
That prompted a warning Thursday from Iran's supreme leader, Ayatollah Khamenei, that Tehran would destroy Tel Aviv if Israel were to attack its nuclear facilities.
Obama also warned the Syrian government that using chemical weapons against opposition forces or allowing such weapons to be obtained by terrorists would be a "game-changer" in terms of U.S. involvement in the conflict. His administration has been criticized for not providing military aid to the Syrian opposition.
On Wednesday, Obama sought to assure Netanyahu and Israelis of his commitment to their security and to strengthen what have been strained personal and working relationships between the two men.
In what Netanyahu called a key development, the leaders announced new talks on extending U.S. military assistance to Israel for another 10 years past the current agreement, which expires in 2017.