Polling stations across Iran opened Friday morning for voting in the country's presidential election which pits incumbent President Mahmoud Ahmadinejad against three other candidates.

Following are the profiles of the four candidates:

-- Incumbent President Mahmoud Ahmadinejad

Ahmadinejad is considered a representative of the country's ultra-conservatives and a close disciple of Supreme Leader Ayatollah Ali Khamenei.

Ahmadinejad was born in a blacksmith family in 1956 in the village of Aradan near Garmsar in the northern Iranian province of Semnan. He holds a PhD in civil engineering from Iran University of Science and Technology.

Ahmadinejad joined the Islamic Revolution Guards Corps voluntarily after the 1979 Islamic Revolution, and also reportedly served in covert operations during the 1980-1988 Iran-Iraq war.

Before taking office as president in August 2005, Ahmadinejad was the governor general of Ardabil province in 1993-1997, and mayor of Tehran from June 2003 to August 2005.

During Ahmadinejad's presidency, Iran continues to speed up its nuclear program and has refused to end uranium enrichment despite UN Security Council resolutions calling for it to do so.

Ahmadinejad also maintains a hard line with the United States and Israel. In response to U.S. President Barack Obama's recent diplomatic overtures, Ahmadinejad said Iran wanted "real changes" from Washington and supported dialogues based on mutual respect and justice.

Ahmadinejad has dramatically increased government spending and has supported subsidies for lower-income families. But as Iran is suffering from soaring inflation and high unemployment, his track record in the economic field has been a frequent target of criticism.

-- Former Prime Minister Mir-Hossein Mousavi

Mousavi is a leading representative in Iran's reformist camp and is considered by many observers as the main challenger to Ahmadinejad.

Mousavi was born in 1941 in the city of Khameneh in the northwestern Iranian province of East Azerbaijan. He holds a master 's degree in architecture from Shahid Beheshti University.

Mousavi is an Iranian reformist politician, painter and architect who served as Iran's prime minister from 1981 to 1989. Mousavi is currently the president of the Iranian Academy of Arts.

He was widely praised for managing the country during the Iran-Iraq war in 1980-1988. After 20-year political silence, Mousavi announced in March his bid to run in the presidential election.

As a reformist politician, Mousavi has repeatedly criticized the incumbent government's economic policy which he terms as alms-based. He also vows to pursue constructive interaction and better relationship between Iran and the world if he is elected as president.

Mousavi also said that he ran for the election to pursue liberty of speech and thought.

-- Former Parliament Speaker Mehdi Karroubi

Karroubi, the current chairman of the National Trust Party, is regarded as a pragmatist reformist in Iran's political scene.

Karroubi was born in 1937 in the city of Aligoudarz in the western Iranian province of Lorestan. He holds a bachelor's degree in Western philosophy from Tehran University.

Karroubi was the speaker of the Iranian parliament from 2000 to 2004, and from 1989 to 1992. He was among the candidates for the presidential election in 2005, when he finished third in the vote count.

Karroubi vows that he would change Iran's executive mode if he is elected as president, saying that Ahmadinejad's statements have caused many problems that make Iran pay a lot.

Admitting that changing Iran's gloomy image in the international society is an arduous task, Karroubi says he would prefer "good diplomacy" in foreign policy and try to establish "logical, wise and proud" relationship with other countries.

-- Former Revolutionary Guards Chief Mohsen Rezaei

Rezaei, currently the secretary of the Expediency Discernment Council, is considered by many observers as a moderate conservative candidate in the upcoming presidential election.

Rezaei was born in 1954 in the city of Masjed Soleyman in the southwestern Iranian province of Khuzestan. He holds a PhD in economics from Tehran University.

Rezaei, who was Commander of the Islamic Revolution Guards Corps from 1981 to 1997, also ran as a candidate in the last presidential election in 2005, but withdrew on June 15, 2005, just two days before the election.

Officially adopting "economic rescue" as a campaign slogan, Rezaei says he intends to bring a revolution in the Iranian economy as Ahmadinejad has driven the economy to the edge of a "precipice."

Rezaei said he is ready to have interactions with foreign countries, including the United States, on preserving security, peace and tranquility in the region.

Rezaei said that, in order to help address Western concerns over the nature of Iran's nuclear activities, he would continue Iran's uranium enrichment within the framework of an international consortium, which may include the United States, Russia and the European countries.

Source: Xinhua