"We need to make sure no one has the capability or the power to commit destruction against us," Ehud Olmert said on Tuesday in what could be a veiled warning of potential Israeli military action against Iran.
"The Jewish people and the very existence of Israel" are Iran's targets, Olmert said, "and we don't see enough of a response from the world".
In a satellite relay to a convention of the Anti-Defamation League, a pro-Israel group, Olmert, who is in the midst of putting together the final pieces in a new Israeli government, responded firmly to Mahmoud Ahmadinejad's frequent rhetorical jabs at Israel.
Olmert said he takes the threats by Ahmadinejad to erase Israel from the map "very seriously".
"We do not take it lightly," Olmert said, speaking from Jerusalem. "We are powerful and able to defend ourselves."
Olmert has urged the international community to work against Iran's nuclear programme, saying Tehran's ambitions threaten not only Israel but all of Western civilisation.
Israel has long identified Iran as its biggest threat, and these concerns have grown amid repeated calls by Ahmadinejad for Israel's destruction.
Ahmadinejad has repeatedly
called for Israel's destruction
On top of the threats the Iranian leader has denounced Israel as a "fake regime".
In his speech to the conference Olmert reiterated his determination to establish a "new reality" in the region, either through negotiations or unilaterally.
He said Israel would separate itself from the Palestinians on parts of the West Bank, affording the Palestinians a state and a better life.
"We want to end this cycle of violence," he said, referring to the decades-old conflict between Arabs and Israel.
Olmert also praised George Bush, the US president, saying Israel was "in good hands" when it relied on him.