Al-Akhbar newspaper, lashed out at Israel after its president, Shimon Peres, warned at the weekend that an attack on Iran is becoming increasingly likely.
Israel, Iran's arch-enemy, was "bound to collapse," Ahmadinejad said.
"Iran's capabilities are increasing and it is progressing, and for that reason it has been able to compete in the world. Now Israel and the West, particularly America, fear Iran's capabilities and role," he said.
"Therefore they are trying to gather international support for a military operation to stop (Iran's) role. The arrogant should know that Iran will not allow them to take any action against it," he said.
Ahmadinejad, who repeated Iran's frequent denials that the Islamic state is not seeking nuclear weapons and that its atomic programme is for peaceful purposes only, added that Washington wanted to "save the Zionist entity, but it will not be able to do so."
"This entity (Israel) can be compared to a liver transplanted in a body that rejected it," he said. "Yes it will collapse and its end will be near."
Peres warned in an interview aired by Israel's privately-owned Channel Two television on Saturday that an attack on Iran was becoming "more and more likely."
He followed this up in comments published on Sunday by the Israel Hayom daily, saying: "The possibility of a military attack against Iran is now closer to being applied than the application of a diplomatic option.
"We must stay calm and resist pressure so that we can consider every alternative," he added.
"I don't think that any decision has already been made, but there is an impression that Iran is getting closer to nuclear weapons," Peres added.
The spike in tension between Israel and Iran comes ahead of the expected release Tuesday or Wednesday of a report into Iran's nuclear programme by the International Atomic Energy Agency (IAEA) nuclear watchdog.
Previous IAEA assessments have centred on Iran's efforts to produce fissile material -- uranium and plutonium -- that can be used for power generation and other peaceful uses, but also for the core of a nuclear warhead.
However the new update will focus on Iran's alleged efforts to put the fissile material in a warhead and develop missiles to carry them to a target.