A tense exchange unfolded at a major security conference in Munich on Sunday, when Israel's Prime Minister Benjamin Netanyahu once again scolded Iran, which he described as the largest threat to Middle East security.

Holding up a component from what he said was an Iranian drone, Netanyahu warned Tehran not to test Israel's resolve.

Iran responded by accusing Israel of being the main aggressor in the region.

Al Jazeera's David Chater reports from Munich.