In some of his toughest comments yet on Tehran's nuclear drive, President Obama also warned Israel and Iran should take seriously possible US action against Iranian nuclear facilities if sanctions fail to stop the country's atomic ambitions.
"I think that the Israeli government recognizes that, as president of the United States, I don't bluff," President Obama told the Atlantic Monthly magazine.
"I also don't, as a matter of sound policy, go around advertising exactly what our intentions are. But I think both the Iranian and the Israeli governments recognise that when the United States says it is unacceptable for Iran to have a nuclear weapon, we mean what we say."
Mr. Netanyahu arrived in Canada early on Friday ahead of discussions on Monday with President Obama at the White House, and the Israeli leader this week said Iran's nuclear program will be "at the center of our talks."
Mr. Netanyahu's government has maintained that all options remain on the table with regard to action on Iran, but Obama issued a blunt warning against an premature strike.
"At a time when there is not a lot of sympathy for Iran and its only real ally (Syria) is on the ropes, do we want a distraction in which suddenly Iran can portray itself as a victim?" President Obama said.
Even if Israel were not a specific target of Iran's wrath, President Obama said "it would still be a profound national-security interest of the United States to prevent Iran from getting a nuclear weapon."
He also spoke of the "profound" risks of an Iranian nuclear weapon falling into terrorists' hands, and warned of "the prospect of a nuclear arms race in the most volatile region in the world, one that is rife with unstable governments and sectarian tensions.
"And it would also provide Iran the additional capability to sponsor and protect its proxies in carrying out terrorist attacks because they are less fearful of retaliation," he said.