Israel's defense minister says the world must prepare to "swiftly and firmly" stop Tehran from acquiring atomic weapons and setting off a regional nuclear arms race.

In a thinly veiled reference to a military strike, Ehud Barak acknowledges that such an operation would be "complex, risky and unpredictable."

He warns that a nuclear Iran "would be far more complex, dangerous and immeasurably more costly," both in terms of human lives and financially.

At the Israeli Defense Ministry's annual Independence Day reception late Thursday, Barak warned that "Saudi Arabia, Turkey and even Egypt would be forced to join the race."

He also predicted a nuclear Iran would "assertively" back anti-Israel militants in "sowing terror in the region and throughout the world."

Iran denies it aims to build nuclear weapons.