Iranian President Mahmoud Ahmadinejad was visiting his close ally President Hugo Chavez in Venezuela on Monday amid growing tensions with the U.S. over Tehran's nuclear program and a death sentence against an American man convicted of working for the CIA.
The two leaders planned to meet in Caracas in the afternoon on the first leg of a four-nation tour that will also take Ahmadinejad to Nicaragua, Cuba and Ecuador.
His visit comes after the U.S. imposed tougher sanctions against Iran over its nuclear program, which Washington believes Tehran is using to develop atomic weapons.
Adding to the tensions, Iranian state radio reported on Monday that a court in Iran has convicted an American man of working for the CIA and sentenced him to death.
The conviction and Ahmadinejad's South American visit come as the new U.S. sanctions cause real economic pain in Iran, the country spooks oil markets with threats to international shipping, and an election in two months widens political divisions at home.
The United States denies Arizona-born 28-year-old Amir Mirza Hekmati is a spy, and has demanded his immediate release.
Iran has aired a televised confession, denounced by Washington, in which Hekmati said he worked for a New York-based video game company designing games to manipulate public opinion in the Middle East on behalf of U.S. intelligence.
"Amir Mirza Hekmati was sentenced to death ... for cooperating with the hostile country America and spying for the CIA (Central Intelligence Agency)," ISNA news agency quoted judiciary spokesman Gholamhossein Mohseni-Ejei as saying.
Separately, two diplomats in Vienna, where the U.N. nuclear watchdog is based, said Iran had finally carried out a long-planned step to begin enrichment of uranium at a site deep under a mountain near the Shiite Muslim holy city of Qom.