The Iranian president has called on the US to withdraw its troops from the Gulf region and Afghanistan.
"The region has no need for alien troops and they should return home and let the regional states take care of their own affairs," Mahmoud Ahmadinejad said in a speech marking the country's annual Army Day on Sunday.
"They must leave the region and this is not a request but an order, and the will of the regional nations," he said.
He said the deployment of US and Nato troops in Iraq and Afghanistan under the pretext of fighting terrorism had not only failed, but also increased insecurity in both countries.
Israel will 'collapse'
The president also said that Israel, the "main instigator of conflict" in the Middle East, was on its way to collapse and that regional powers wanted it uprooted.
"This is the will of the regional nations that after 60 odd years, the root of this corrupt microbe and the main reason for insecurity in the region be pulled out," Ahmadinejad said.
He said that except the "Zionist regime (Israel)," Iran considered all other countries as "friend and brother" with whom the Islamic state wanted peaceful co-existence.
On the day that Iran was exhibiting its latest military hardware, Ahmadinejad vowed that the country would use all its military potential in case of any armed aggression.
Ahmadinejad's comments came a day after he called for the formation of a new international body to oversee nuclear disarmament during a two-day summit on civilian nuclear energy in Tehran.
The summit, which is continuing on Sunday, is seen as a counterpoint to a major conference in Washington earlier this week, in which Barack Obama, the US president, outlined his nuclear strategy.
Iran criticised the 47-nation nuclear security summit on the grounds that the US holds one of the world's largest stocks of nuclear weapons.
Iran was not invited to the conference as the US fears its nuclear programme could be a cover for the production of atomic weapons.
Tehran says it is entitled to continue work on its controversial uranium enrichment programme. It strongly denies it is seeking nuclear weapons, saying its atomic programme is for meeting civilian energy needs.