Iranian president Mohammad Khatami is holding talks in Zimbabwe with President Robert Mugabe and other senior leaders of the ruling Zanu PF Party.
President Robert Mugabe has few friends left in the international arena, and he has hailed Iran as a "critical partner."
Iran, which recently provided more than $40 million in loans to Zimbabwe, mostly for agricultural and communications equipment, has had close relations with the Harare government since Mr. Mugabe came to power in 1980.
Economists say Mr. Mugabe will be particularly interested in receiving expanded credit for a regular supply of fuel from oil-rich Iran.
At present fuel is available at irregular intervals, with some parts of the country, particularly smaller towns, without any at all.
At a banquet in honor of the Iranian leader shortly after his arrival, Mr. Mugabe said Iran was a key partner in Zimbabwe's recent foreign policy drive.
Mr. Mugabe was quoted in the state-controlled Herald newspaper as saying he attaches "great importance" to the visit because it will enable the government to "work towards strengthening and diversifying our relations."
Iran is one of the countries, along with Malaysia and China, which are part of Mr. Mugabe's look East foreign policy drive.
This push towards Asia follows Zimbabwe's growing isolation from the West, which has criticized Mr. Mugabe's clampdown on political opponents and new laws described by human-rights groups as repressive.
Mr. Mugabe told the Iranian leader all foreign troops should be withdrawn from Iraq. He said the West also sought regime change in Zimbabwe because his government had seized white-owned farms during the past five years.
President Khatami visited Zimbabwe's premier tourist resort of Victoria Falls and visited a crocodile farm. Zimbabwe is a large supplier of commercially produced crocodile skins. According to the state-controlled media, President Khatami will meet some leaders of the small Muslim community in Zimbabwe before he leaves.
At the end of his three-day visit to Zimbabwe Wednesday, President Khatami goes to Uganda, the last stop on his seven-nation African tour.