Former President Mohammad Khatami, who oversaw a thaw in ties with the West when in office from 1997 to 2005, announced on Sunday he would run for the presidency again in the June election.

Here are some key facts about the country:

ECONOMY: Holds world's second biggest reserves of both oil and gas, and world's fourth largest oil producer. Oil accounts for roughly 80 percent of hard currency income. Critics say the government has not saved enough when oil prices were high to maintain spending now the price has dropped to $40 barrel from $147 in July.

-- Many Iranians complain about high inflation, which hit almost 30 percent last year but which has since dipped, and rising unemployment. Analysts say the economy will be a major focus of the June 2009 election between President Ahmad Ahmadinejad and Khatami. Other candidates have also declared.

-- Iran's main exports aside from oil include carpets and pistachio nuts but they are relatively modest. Central bank figures for the year to March 2008 showed oil and gas exports at $81.8 billion compared with non-oil exports of $15.6 billion.

-- Some figures from 2007 - GDP: $271 billion; Growth: 7.1 percent.

* COUNTRY DETAILS:

CAPITAL: Tehran.

POPULATION: 71.3 million. (2007)

ETHNICITY: Persian 51 percent, Azeri 24 percent, Kurds 7 percent, Gilaki/Mazandarani 8 percent. There are also Lur, Arab, Baluch and Turkmen minorities.

RELIGION: The Shi'ite sect of Islam predominates (89 percent), with some Sunni Muslims (10 percent). There are also Christian, Jewish, Zoroastrian and Baha'i minorities.

OFFICIAL LANGUAGE: Persian/Farsi (official) and minority languages (Kurdish 7 percent)

AREA: 1,684,184 sq km (636,364 sq miles), or roughly three times the size of France.