MUNICH — Israeli Prime Minister Benjamin Netanyahu on Sunday issued a stark warning to Iran, saying his nation was prepared to go to war if the Iranians continue to test Israeli red lines in Syria.

Brandishing what he said was a fragment of an Iranian drone shot down over Israeli territory last week, Netanyahu cited Iran’s efforts to “colonize” Syria with a permanent military base and use the war-ravaged nation as a launch pad for operations in Israel.

“Israel will not allow Iran’s regime to put the noose of terror around our neck,” he said. “We will act without hesitation to defend ourselves. And we will act, if necessary, not only against Iranian proxies that are attacking us but against Iran itself.”

The warning came in a widely anticipated speech Netanyahu delivered to the Munich Security Conference, the world’s most prominent gathering of its type. The saber-rattling address was followed later Sunday with a speech by Iranian Foreign Minister Mohammad Javad Zarif.

“Mr. Zarif, do you recognize it?” Netanyahu asked as he held the drone fragment aloft. “You should. It’s yours. You can take back with you a message to the tyrants of Tehran: Do not test Israel’s resolve.”

In his own speech, Zarif dismissed Netanyahu’s address as a “cartoonish circus.”

The Iranian foreign minister cited “almost daily incursions into Syrian airspace” by Israeli aircraft, its strikes against targets in Lebanon and its occupation of Palestinian lands.

“Israel uses aggression as a policy against its neighbors,” he said. He suggested that Netanyahu was deliberately raising tensions as a way to distract from his troubles at home.

Netanyahu has for years been making dire predictions about the potential for war with Iran, a regional power that he Saturday described as “the greatest threat to our world.”

But the dynamic is different now: Netanyahu is weakened domestically, with police investigators recommending he should be charged with corruption. He also feels emboldened abroad, as he finds new allies in President Trump and in an Arab world that has been increasingly willing to put aside its longtime enmity toward Israel to oppose mutual rival Iran.

The latest escalation of Middle East tensions began last weekend when Israel shot down the Iranian drone that had crossed into its airspace. Israel carried out airstrikes in Syria in retaliation for the incursion, but one of its F-16 fighter jets crashed while under fire.