Iranian President Mahmoud Ahmadinejad has started a five-day Latin American tour that U.S. officials have called a sign of desperation for the country heavily sanctioned over its controversial nuclear program.

Mr. Ahmadinejad arrived Sunday evening in Venezuela, and was met at the airport by that country's Vice President Elias Juau. He smiled and waved to the crowd, but did not make any remarks before driving away. He is scheduled to meet Monday with his longtime ally, Venezuela's President Hugo Chavez.

The Iranian president also will make stops in Nicaragua, Cuba and Ecuador.

In recent years, the Iranian president has courted leftist, populist and anti-American Latin American leaders, particularly Venezuelan President Hugo Chavez, much to Washington's dismay.

On Friday, U.S. officials urged Latin American countries not to deepen their ties with Iran. A State Department spokeswoman accused the Iranian government of being “desperate for friends” and of,what she called “flailing around” to find new allies.

While on his trip, Mr. Ahmadinejad also will attend the inauguration of Nicaraguan President Daniel Ortega.

The United States is expelling a Venezuelan diplomat amid reports that she discussed possible cyber-attacks on U.S. soil while she was stationed at her country's embassy in Mexico.

The State Department said Sunday it had declared Livia Acosta Noguera persona non grata and given her until Tuesday to leave the country.

There was no immediate reaction from the Venezuelan government.