United States Vice President Joe Biden has issued another warning to Iran over its nuclear programme.
Mr Biden said on Monday that President Obama was not bluffing when he said the US would not allow Iran to acquire nuclear weapons.
"We're not looking for war. We're ready to negotiate peacefully . But all options including military force are on the table," said Mr Biden in a speech to the American Israel Public Affairs Committee.
"While that window is closing, we believe there is still time and space (for diplomacy)," he added.
Mr Biden said that a nuclear bomb in Iranian hands would be an "existential threat" to Israel, pose danger to other US allies in the Middle East and would destabilize the world.
"We have a shared strategic commitment. Let me make clear what that commitment is: It is to prevent Iran from acquiring a nuclear weapon, period," he said to loud applause.
Talks involving Iran and Britain, China, France, Germany, the United States and Russia in Kazakhstan about its nuclear work ended last week with an agreement to meet again.
Iran insists its nuclear programme is peaceful, for domestic purposes.