By Hugh Bronstein
CARACAS (Reuters) - Venezuelan President Hugo Chavez, on his way to Cuba for a fourth round of chemotherapy on Saturday, dismissed an international court ruling that cleared a key opposition candidate to run against him in 2012.
The charismatic leftist has led Latin America's top oil exporting country since 1999 and wants to stay in office until at least 2025 to consolidate his self-styled "revolution."
The opposition -- galvanized by a recent decision from the Inter-American Court of Human Rights that cleared rival Leopoldo Lopez to run against Chavez -- aims to bring that revolution to an end in the October, 2012, election.
The court is part of the Organization of American States, or OAS, and its decisions are supposed to be binding. But Venezuela may keep Lopez out of the campaign just the same.
Despite being treated over the last three months for cancer, Chavez was in classic form on Saturday, breaking into song during marathon public appearances. In televised comments, he laughed the court decision off with a play on words.
"One of my haircuts is worth more than this court," he said to laughter from an audience of supporters. In Spanish, the word "corte" means "court" as well as "cut", as in haircut.
The 57-year-old leader has shaved his head since entering chemotherapy and often jokes about his new look. His government issued a statement on Friday dismissing the Lopez ruling as a politically motivated violation of Venezuelan sovereignty.
Chavez remains Venezuela's most popular politicians despite rampant crime and one of the highest inflation rates in the world. In June he underwent surgery in Cuba to remove a tumor in the pelvic area, throwing added uncertainty into Venezuela's upcoming political season.
TOUGH CAMPAIGN AHEAD
Centrist candidate Lopez was banned from politics by Venezuelan authorities who accuse him of corruption.
The 40-year-old centrist made his name as mayor of the wealthy Chacao district in Caracas. He was favored to go on to win the race for mayor of the whole city in 2008, but he was blocked by Chavez's comptroller general.
Accused but not tried for corruption, Lopez was barred from seeking public office until 2014. He says the accusations are trumped up and called it unconstitutional to suspend him from politics without first giving him a trial. The court agreed.
Chavez says he will soon be done with chemotherapy and promises to be fit for a rigorous campaign next year.
"I will go to Cuba this afternoon," he said. "Early tomorrow I will start the fourth round of chemotherapy, which will most likely be the last."
The president, who had the constitution changed to allow perpetual re-elections, said he expected to return to Venezuela by the middle of the week after about five days of treatment.
The opposition meanwhile aims to elect a unity candidate in February's primary, which Lopez vows to win.
Polls show him toward the top of an opposition field led by Henrique Capriles Radonski, a state governor who promises to emulate Brazil's "modern-left" policy model if elected.
(Additional reporting by Deisy Buitrago)