Venezuelan President Hugo Chavez said Tuesday the cancer he has been battling has not spread, but admitted the chemotherapy treatment he is receiving had left him weakened.

"Chemotherapy hits hard," Chavez said in comments late Tuesday, noting that his body's defenses were down and that he had "areas of weakness" due to treatment he has been receiving in Cuba.

Venezuelan President Hugo Chavezsang, danced and said he intends to stay in power for two more decades as he celebrated his 57th birthday looking ahead to months of cancer treatment.

Chavez rallied a crowd of cheering supporters from the balcony of the presidential palace on Thursday, waving a large Venezuelan flag and briefly wrapping himself in it. He said he expects to lose his hair soon as a result of chemotherapy and that a long process of treatment lies ahead.

Venezuelan President Hugo Chavez, who has returned home after receiving cancer treatment in Cuba, said in an interview published Monday that he will seek "with more strength than before" his re-election to the presidency in 2012.

"I have medical, scientific, human, romantic and political reasons to continue to lead the government and pursue the candidacy with more strength than before," Chavez told Correo del Orinoco newspaper.

A poll in Venezuela says President Hugo Chavez's public approval rating remains at 50 percent and has not significantly varied since his cancer diagnosis.

The Caracas polling firm Datanalisis surveyed 1,300 people earlier this month, giving the poll a margin error of about 2.5 percentage points.

Venezuelan President Hugo Chavez said Friday he has finished his "first cycle" of chemotherapy in Cuba and will begin the second of various phases of treatment.

Chavez vowed to overcome his cancer, saying he is confident of winning re-election next year and staying in power for at least six more years. He spoke in a telephone call carried live on state television during a speech by his vice president, Elias Jaua.

Venezuelan President Hugo Chavez is using Twitter as a tool to govern remotely while he undergoes cancer treatment in Cuba.

In more than 40 messages this week on his "chavezcandanga" account, he has approved money for a Caracas trash collection project, praised plans for a new park and cheered on the national soccer team.

Venezuelan President Hugo Chavez arrived in Cuba late Saturday to begin chemotherapy treatment for his cancer.

Chavez, who was accompanied by his daughter Rosa, will stay there an undisclosed period of time.

Venezuelan President Hugo Chavez will undergo new treatment for cancer in Brazil after his June operation in Cuba, Brazil's official news agency reported Friday.

Chavez spoke with Brazilian President Dilma Rousseff to work out details of the treatment that will take place at a Sao Paulo hospital, reported Agencia Brasil, which did not indicate its sources.

A Venezuelan court Wednesday sentenced opposition figure Oswaldo Alvarez to two years in prison for disseminating false information during a television show in March 2010, prosecutors said.

In a statement, prosecutors said Alvarez, a former governor of Zulia state, was convicted for saying that "Venezuela had become a drug trafficking hub."

Hugo Chavez has built an entire career on being Venezuela's one-man political messiah. Now his precarious health appears to be prompting him to look into his inner circle for those he thinks are most capable of managing his socialist revolution while he undergoes cancer treatment.

Those standing out include Chavez's elder brother, his foreign minister, his energy minister and a few trusted military officers, both current and former. They are all time-tested loyalists and committed leftists. Yet if Chavez has his mind set on any particular heir to power, he hasn't yet sent clear signals as to whom it would be.