The president of Iran has arrived in Wednesday in Cuba, the third leg of a weeklong Latin American tour.

Mahmoud Ahmadinejad, who is set for talks with Cuban President Raul Castro, has already made stops in Venezuela and Nicaragua.

One subject at the top of their agenda is likely to be the killing of Mostafa Ahmadi Roshan, a nuclear scientist in a Tehran car bombing – an act that Iranian officials have already blamed on the U.S. and Israel.

Iranian media has speculated that Ahmadinejad may also meet with the 85-year-old Fidel Castro, Raul’s brother, although this has not been confirmed by Cuban authorities.

Iran’s apparent ambition of becoming a nuclear power has Western nations gravely concerned, leading the U.S. to upgrade its already tough sanctions against the Middle Eastern nation. Iran has threatened to block the Strait of Hormuz – a key crude oil shipping conduit – in retaliation for Western sanctions.

U.S. government officials have denied any involvement in the killing of Roshan. However, both Israel and the U.S. have not ruled out the possibility of launching air strikes on Iranian nuclear facilities.

Iran, which has vowed to maintain its nuclear program (which it claims is for peaceful purposes only) is reportedly seeking the support of Latin American nations known to be hostile to the U.S.

Cuba knows all about U.S. sanctions and trade embargoes – it has labored under such restrictions for the past 50 years. In addition, Cuba, like Venezuela and Nicaragua, has defended Iran’s right to develop atomic energy.

Ahmadinejad will next journey to Ecuador on Thursday.