Iran's Deputy Defense Minister Naser Dehqan warned Wednesday against what he called "the enemy's attempts" to influence the upcoming presidential election in Iran, the official IRNA news agency reported.

Urging the Iranian nation to remain vigilant, Dehqan said that "We should make every effort to hold a sound election, under a calm political atmosphere with the high participation of all groups (of Iranian people)," according to the report.

During post-election in 2009, enemies managed to bring some anti-Iran opposition forces together but they were defeated, he was quoted as saying.

Protests gripped Tehran and other Iranian cities after the June 2009 presidential election amid claims of election-rig in favor of President Mahmoud Ahmadinejad.

The enemies have already started their activities to influence the election (which is slated for June 2013), Dehqan said, adding that if some try to destabilize the country once again, they will receive a crushing response from the Iranian nation.

The Iranian reformist groups, led by former president Mohammad Khatami, have set some conditions for participating in the upcoming presidential election, including holding a transparent election and the release of two Iranian opposition leaders, ex- prime minister Mir-Hossein Mousavi and former parliament speaker Mehdi Karroubi, who were put under home custody after the 2009 election.

Also, Iran's influential moderate cleric and former president of the Islamic republic Akbar Hashemi-Rafsanjani has recently put forward the idea of forming a "national unity government" which calls for a moderate government from both conservatives and reformist camps to run the country.

Ahmadinejad, who was strongly supported by the hardliner conservatives in the 2009 election against Mousavi and Karroubi, is planning to back his own candidate independently to push forward his own populist policy which envisages a nationalist- Islamist doctrine.